/SQT/ all questions are stupid edition
I'll start:
this one is for biochemists/molecular biologists, what the flying fuck constitutes a low or high Km value?
old thread is dead >>>8009716
How do I actually use the MIT OCW?
(I mean the physics and chemistry lectures which have no video)
I'm self studying math physics and chemistry for a scholarship test in 2 months, would you mind giving me advice?
And yes, I am retarded for not knowing how to approach this.
>>8022778
>this one is for biochemists/molecular biologists, what the flying fuck constitutes a low or high Km value?
Km is a parameter in the Michaelis Menten equation.
From the equation you can see that when [S] = Km then V = 0.5Vmax.
>>8022953
so (bear with me) if the value is over 0.5 we can assume it is relatively "high" and if it falls below, it is low?
I have 0.98 which according to a paper is high, but my curve looks like a curve for a high Km value
i need to get drunk
>>8022953
>>8022974
pic related
>>8022868
If there are assigned readings, do the readings.
If there is homework and exams, attempt to solve the homework and exams.
What exactly are you unsure about? It's just a load of learning materials
where does our consciousness come from
How do I manage to study all this by june 15th?
(I don't need to master everything, I just need to be able to solve problems fast as fuck. 1hr exam)
I would really appreciate some help, if not the correct place to ask just point me to where I have to go. Thanks
how do I determine for what values of k
[math]
(n^2-1)^p(n-1)^{p+1}+k
[/math] is divisible by n?
>>8022983
That picture is kind of misleading, since the enzymes obviously have different vmaxes. If they had the same vmax, the one with the lower km would just reach it faster.
>>8022778
once when i was a little kid i bought some offbrand oreos, i thought that heating them in the microwave would make them taste better and i set them there for a minute.
The oreos packaging started making sparks and i thought it was cool so i let it happen for the whole minute.
When i opened the door i saw the cookies there without the package.
My question is where did the package go and what happened to its components, where they still in the cookies?
>>8023796
I hope you didn't eat them. I assume they became plasticized oreos,
>>8022778
Doing pure math. Got accepted for transfer to UCLA and waiting to hear from Berkeley. If I get accepted to both which should I take? In grad school I'd be looking to do something with mathematical physics or pure math in geometry, topology, or algebra. I know that UCLA is a good math school and is strong in analysis and number theory which I have essentially no interest in. Their undergrad program looks great though.
Idk the best plan of action here.
was asked on a cs exam about matrix transformation. the matrix was [math]\begin{bmatrix} x \\ y \\ 1 \end{bmatrix}[/math], which was a representation of (x, y). we were suppose to give the 3x3 matrix that would give the transformation to (x + 2, 3y). i think i answered [math]\begin{bmatrix} 2 & 0 & 1 \\ 0 & 3 & 1 \\ 1 & 0 & 0 \end{bmatrix}[/math], but pretty sure that was wrong.. anyone know how to solve this? pretty sure its for image processing
>>8023377
Start by expanding the powers and figure out which term(s) leave a remainder when divided by [math]n[/math].
All the talk about sending micro satellites to alpha centauri at 20% the speed of light, have anyone how they're planning to slow the nigga down once it gets there?
Or will it just be a fly-by?
>>8024286
[math]
\begin{bmatrix}
1 & 0&2 \\
0& 3 & 0 \\
0 & 0 & 1
\end{bmatrix}
[/math]
Would output the vector
[math]
\begin{bmatrix}
x +2 \\
3y \\
1
\end{bmatrix}
[/math]
>>8024128
Both are fine schools. As someone who goes to Berkeley, I'm fairly sure the only difference is location in a lot of ways. Granted, Berkeley is more prestigious in some people's view, but that actually makes very little difference.
I got this question wrong obviously.. can anyone explain what I am misunderstanding in my working? I'll reply to my post with my working on my mini whiteboard.
>>8024344
It's only dirty because it's cheap, I only started using it 3 days ago
How do I find a value of a such that the system of linear equations is inconsistent?
[math]\begin{cases}a + y + 3z = 1\\ x + ay +3z =1\\ x + 2y +az =3 \end{cases}[/math]
>>8024344
is the answer 4? not sure if I worked it out right though. if it is I can expalin it. been a while since highschool maths lol.
>>8024347
it's 10/6 = (10+x)/10
the triangles are similar
>>8024365
>The answer isn't 4, it was a fraction (20/3). I'm revising high school math at the moment, it's actually kinda fun.
oh yeah, sounds like it, I should get back into it one day!
>>8024365
the only reason similarity works is because everything is oriented the same way
>>8024371
Never heard of Euclid or Scalar Coefficient, will look it up now.
So when I do this, should I then always put the larger part of the fraction on top or something?
I want to get a scholarship to study in england, is there one for a good engineering university?
I am from latam.
I am trying to find power dissipated on a voltage dividers resistors.
Is (V^2)/R same as (I^2)*R
Whats a general element of a matrice?
How do you name something attached to a substituent? Say I had a chlorine attached to a carbon attached to the parent chain?
>>8024605
treat it as a single side chain and name it how you normally would
just remember that in organic chem, a name can never be too convoluted
>>8024350
cancel them out
you see that the first and 2nd equations for example both have 3z, so if you minus one from the other, you will remove the z term
do this until you are only left with an a term
you might need to substitute somewhere but it's not hard
>>8024611
Thanks
>>8024325
>how they're planning to slow the nigga down once it gets there?
They use sails for propulsion, so presumably the stellar wind from the approaching star will slow them down.
>>8022778
Question for Biologists/Biochemists
How do you analyze genes? How do you extract DNA, how do you know where a gene ends, how do you look at it? Basically how does gene engineering work and why can't we just change our genes however we like?
>>8024347
>60x
should be 6x
>>8024344
arctan(6/10) to get angle at point A (I'll call that angle 'a').
tan(a)=10/(10+x)
rearrange to: x=10/(tan(a)) - 10
Learning to trig is way more useful than learning scalar coefficient, but scalar coefficient is pretty simple. 6/10=0.6. 10/0.6=16+2/3. 16+2/3-10=20/3
>>8024651
Oh god I'm retarded
Just got a new processor and can't hit 30% even.
What are some good science-related programs (e.g. simulation etc.) that make heavy use of the CPU while teaching you something too? Preferably molecule related and such.
Is there maybe a program where you can analyze large macromolecules like hormones labeled with their active sites and other such details?
>>8024650
genetic analysis is generally mathematics, calculating the probability that an allel will find its way on a certain number of individuals, etc (ofc it is much more than that)
extracting dna, lets see, you grab a fruit fly, you mash it, you put it in an eppendorf tube, you add buffer, you shake dat_bad_boy, you add a bunch of other chemicals, centrifuge here and there, you get fat as a pellet and the dna in the liquid (that i remember), and theoretically you should have dna juice
if you wanna amplify it, you add a primer, dna polymerase and do some pcr and you get a bunch of dna copies which you can analyse via gel electrophoresis
a gene is a hard thing to describe imagine a long string, and in this string you have a starting sequence, and you have pieces of dna (bases) that code for something useful usually (proteins), there are many empty spaces between these sequences, and the ones that are not empty will be translated to something, then comes mRNA and does a copy of this, this copy is then translated with the help of tRNA into aminoacid chains and then proteins
https://en.wikipedia.org/wiki/Central_dogma_of_molecular_biology
you can change the genes ofc, rape the shit out of them, but you have countless cells and a myriad other factors coming into play, plus theres also "ethics" which some people care about. we're getting there though, look into cas9/crispr
hope this was of some help, if im wrong, someone correct me
>>8024128
>I know that UCLA is a good math school and is strong in analysis and number theory which I have essentially no interest in
It doesn't really matter at all for you. Try to visit both campuses and decide where you'd rather live.
>>8024756
Holy shit I just realized I'm fucking stupid and don't get Biology at all
I have a programming problem, but it's really a math problem in disguise, so it's not really suitable for /g/:
I have a function which takes a byte as input and checks it against all cyclic permutations of another byte. This works fine, until I try to introduce starting offsets to one of the strings, and then I'm lost.
pic related is the function. In this case, the problem is in the first half of the function. I am trying to check for a given surface by checking the bit and the two adjacent bits (with curcular shifts) to see if they are free. (1 = not free, 0 = free). each bit position corresponds to a free adjacent cell to a given tile on a 2d orthogonal grid.
So in this case, my input string is an arbitrary byte, my comparison string is the cyclic permutations of 00000111, (cyclically) offset by one so it is centered on the bit of the input we are concerned with.
The function does not work correctly in its current form, and I think it has to do with how I'm approaching the problem. Any math people able to help me here?
>>8024664
using latex inside [math] or [eqn] blocks
>>8024816
people tend to think biology is just memorising the name of things, while that is partially in the right, it is also much more
biology is too broad, therefore it has many branches, if you're interested just read introductory textbooks like campbell biology, then see where that takes you
just think chromosomes is highly compact dna, which then gets copied and that gives you proteins which are the worker bees of organisms
Guys I have a 2 samples each with 2 features measured. How do I test the p-value to see how likely it is that the 2nd sample differs from the first? Wherever I read about t-test/z-test, they keep referring to population.. in my case is the 1st sample the population? Cause technically it's a sample, and both samples have the same number of data points (20)
the shear stress graph in a monodimensional beam represent forces parallel or perpendicular to the length of the beam???
>>8024974
ok i decided on 2-samples paired t-test, hope it's good
>>8024751
>Just got a new processor and can't hit 30% even.
Curious, what system did you get? (sorry no answer to your question)
>>8025025
> shear
Perpendicular
So, uh, how much mathematics would I have to know that the example in the link makes sense?
https://en.wikipedia.org/wiki/Abstract_nonsense
I'll be transferring to a university from a community college. What year would I be considered? Second or third year?
Can a computer engineer work on robotics field?
I'm currently taking an intro to proofs class and came upon pic related. I'm pretty sure I negated the statement correctly and I can't understand why the negation is false.
I think the negation is true because for every natural number, I can find a real number to make that statement true. Thoughts?
>>8025355
You've written it correctly (though 'such that' is unnecessary), but the negation is read 'there is a real number x such that all natural numbers are smaller than or equal to the absolute value of x' which is obviously false. You switched the order of the quantifiers around, which you cannot do unless they are the same.
>>8025385
Thanks anon, that makes sense.
>>8022778
Just finished a course which dealt heavily with MM kinetics.
Km is essentially a dissociation constant -- although it classically is considered as different than Kd, but that's an easy way to conceptualize it. As the concentration of substrate increases, reaction velocity approaches a maximum (Vmax, denoted as 1.0). Km, like a dissociation constant, is the point of concentration of substrate in which velocity is 1/2 of Vmax, or 0.5.
What constitutes high or low Km is centered around the protein's affinity for its ligand -- which is typically the experimental substrate. Low Km means the enzyme has a higher affinity for substrate, and therefore approaches Vmax more rapidly w.r.t. increases in [Substrate].
Hope that helps.
>>8024650
The reply you got is mostly accurate, but I can give you a more concise and simple answer to each question:
There are many ways to analyze genes, and the method is chosen based on what information you're attempting to collect. I can tell you about some specifically if you're still here and curious about certain techniques.
Extracting DNA is typically done by cell fractionation and then centrifugation. Nucleic acids will occupy their own "band" in the test tube as determined by sedimentation characteristics such as density. Think of how oil and water separate.
The end of a specific gene is coded for by highly conserved "stop" codons -- UAG, UGA, or UAA. These are read by the molecular machinery to terminate the process, such as transcription of a gene into mRNA.
You can look at genes several ways. Analysis of genes can be done by running them on a gel, as stated by the anon here >>8024756. Or if the sequence is known, you can engineer a complementary sequence, stick those single strands of nucleic acid to a glass surface, then wash the experimental DNA solution over top of it. Your gene sequence of interest will bond specifically to form double stranded DNA. This is called a DNA array. Again, there are other methods if you want to know specifics.
We can change genes, but there are plenty of issues surrounding the idea. A typical way is by taking the native DNA of a bacterium (called a plasmid), such as E. Coli, and inserting the gene of interest into it, then using viral machinery to insert into the patient and replicate the new, desired genes.
Those are the short answers. It's important to know that the genetic code is filled with non-coding portions, ie, sequences that are never transcribed into mRNA and translated into proteins. But these sequences are important because we can use them to understand where specific genes occur in chromosomes, and target them to be removed, replicated, studied, etc.
>>8025239
Yes.
Machine vision for one has a lot of low level work.
New Sensors in general are always being developed
>>8025444
>molecular machinery
This is another thing I don't get. "What" exactly "reads" the genes? Or more precisely how do genes even work? How do they decide when to use which sequence of the DNA and for what? How for example is an organs grown? A heart, a brain, a lung? How do they know which macroshape to take? And with that I mean I don't even understand what "they" are.
Shit I'm so fucking stupid.
Brainlet herte,
what rule is this?
[math]
7^{k}-2^{k} \equiv 7^k-7^k2^k+7^k2^k-2^k
[/math]
How difficult would taking Differential equations and Calculus 3 at the same time B if you've aced calculus 1 and 2?
>>8025470
I dunno
That you can add 0 and it doesn't change the value?
>>8025355
The negation is that there exists a real number x whose absolute is greater than or equal to any natural number. Assume this is true. Then 1+ceiling(|x|) is a natural number. But 1+ceiling(|x|) must be greater than |x|. So there is a natural number greater than x. This is a contradiction of our assumption so the assumption must be wrong.
>>8025468
The central dogma of molecular biology is:
DNA --(transcription)--> mRNA --(translation)--> Protein
Genes (DNA) are coded by four nucleic acid bases, ATGC. It's important not to get hung up with thinking of these as "letters." In reality, they are large molecules with unique structures. The elements they are made of have different charges and characteristics which allow them to be recognized by necessary enzymes, such as the ones that transcribe DNA into mRNA. Genes that are destined to become proteins are typically unique and actually nonsensical sequences relative to the enzyme until they reach the mRNA stage -- where three letter codons of AUGC denote specific amino acids to be bound together into proteins. There are common promoting sequences at the "start" of coding genes which enzymes have evolved to recognize through chemistry and binding characteristics. Transcription and translation are really just chemical reactions that occur wherever the right enzyme can bind, and it will continue until it hits a stop sequence (in DNA) or a terminator structure (mRNA). Coding genes are sequences that follow promoters, this is how the cell "decides" which genes to use. The way that organs form their shapes is denoted by genetic code and the characteristics of the proteins that ultimately form the organ. A liver for instance, is coded by chromosomal genes initially. It starts small in development, as a cluster of proteins transported to and binding in a specific area, and grows with the rest of the body in relation to necessity. Systems such as cellular signaling are used to activate certain genes in times of need, like human development.
You are asking a lot of great questions which are too complex to answer simply, and you would be best served studying something like biochemistry to give yourself context. These mechanisms are nothing more than inevitability, determined by chemical physics and thermodynamics. They've evolved in complexity over time.
Trying to learn about hyperbolas.
I am told that [math]y = \frac{1}{x}[/math] is a hyperbola, which it looks like rotated 45 degrees about the origin. I am also told that [math] x^{2} - y^{2} = 1 [/math] is the equation for a basic hyperbola. What kind of algebraic manipulation is necessary in order to see the first equation in terms of the second equation?
>>8025529
Ah this answers a lot, thank you.
So it's enzymes that decode DNA?
But where do enzymes comes from then?
Can you recommend me some beginner books for me to get into biochemistry?
>>8022778
Say you have one day off every week, and the rest of your week is filled with stressful mental work and moderate exercise -- is it normal to feel very fatigued on your day off?
>>8025567
Yep. Cellular machinery refers to enzymes (nearly all enzymes are made of protein). All amino acids, and therefore proteins, come from mRNA, which is coded by DNA. Similarly to how the nucleic bases AGTC have unique characteristics, the 20 amino acids that are coded by mRNA have unique chemical compositions which can be arranged in essentially limitless ways to achieve many tasks. Pic related is a visual example of the protein "Kinesin." You can see how it appears to be walking across another protein. In reality, it binds to a spot on the protein inevitably because of its unique make-up (maybe one amino acid in the "foot" is positively charged and an amino acid on the target protein is negatively charged, for instance), and then the change of the system after it binds causes it to swing into the next position, and so on. I think it's important to take "intelligence" and purpose out of the question when considering these things. Enzymatic activity, like the enzymes tasked with decoding genes, is as unsurprising as watching a ball roll down a hill once you understand the make-up of the protein and its target.
I would recommend studying biology up to genetics and cell and molecular biology, and all of chemistry and chemical physics. Once you get up to the level of biochemistry, look for Voet, Voet, and Pratt -- Fundamentals of Biochemistry. I liked that one a lot.
>>8025567
I was the first guy who replied to you, I recommended you campbell biology, to understand biochemistry you will need some knowledge about general chemistry, as well
http://gen.lib.rus.ec/book/index.php?md5=66F6EE344E4EDE7EFDB0C50EE0BBA420
it's a lot of info to process at once, try khan academy first, if you're still interested then start reading biology -> genetics -> biochemistry
if you still wanna jump into biochem, try lehninger biochemistry
>>8025355
Here we use | instead of such that!
what is love?
>>8025768
Dunno, i have a bad DSM
So I am finishing up a term long research project, and I have a bit of an issue. This project deals with high school dropout rate. I have Gender and Ethnicity as variables (Which are divided into male/female white/black/etc)
I found the dropout rate for each of the schools I am examining fine, but when I look to the actual number of students that dropout I hit a brick wall. The resource I found only lists students who dropped out above ten, anything <10 is marked as "<10". This is prevalent across gender and race, with only the schools who got above that threshold warrent a number. I have no idea what to do, since I have to run a correlation and regression with my variables and all these <10s are really messing with me. Suggestions?
http://www.ncpublicschools.org/docs/research/dropout/reports/2014-15/7-13-by-lea-gender-race.pdf
Here is the resource in question
>>8026069
Throw them into Excel or your analysis software of choice and divide everything by ten, take the <10's to be equal to 1. Everything will scale the same way, and you can denote that the scale of the regression is 10's of students. Of course <10 means it could literally be any number 0-9, but you've gotta work with what you have (assuming you can't find better data elsewhere) and create some uniform statistics.
If homeostasis is at 98°F then why does almost everyone start sweating at temperatures at or exceeding 80°F ?
>>8026079
Alright thanks. I was just afraid of my professor bitching at "lol ur lazy why didnt u find the data" or some shit.
I'll just throw a paragraph in my paper about it since Virginia/California/Flordia all seem to ignore things below ten
>>8026081
At 80 degrees F, there is enough energy in the environment (in the form of heat) to be transferred to our skin and peripheral tissues (which are not at body temperature of 98 degrees F). Sweat helps keep those surfaces cool with evaporation and therefore prevent internal overheating. There's actually almost always water being evaporated out of your skin, even at lower temperatures when you don't feel sweaty -- the perspiration is just too insignificant to notice.
Are there any known biological processes that don't involve either baryons, photons, or electrons?
I've been learning about particle physics, and it seems like most living things just ignore things like neutrinos and muons.
>>8022778
How hard is cryptography guys? I have a background in elementary number theory and a little abstract algebra, and that's it. I'm taking a class next semester and i want to not fail, recommend me some readings guys
If there are 100 chairs, and 99 people, how many combinations can there be, with no extra stipulations?
I keep coming to [tex] 100! / 1! [/tex] but I think it's wrong. I was being stupid and thinking it equals 100, but then i realised 100! is a big number, and a big number divided by 1 is still a big number.
My waifu thinks it is 100! / 99!
What's the real answer, sci?
>>8026282
Don't use factorials.
You should be doing 100 nPr 99
If I remember this shit correctly.
>>8026265
do you know how to factor large primes?
If there were 100 chairs, and 98 people, it would make sense because
[math]100! / 98! [/math] yields a reasonable answer to the problem, i.e. not 100!.
I have a circuit, pic related assuming that the 40ohm resistors, are in fact motors. and the 2 resistors to the right hand side are variable resistors.
Will varying these variable resistors, change the speed of the motors?
>>8026282
It's 100! assuming everyone's special
your waifu's right if we assume no one is
>>8026310
yes.
Speed is determined by current.
So lets say you lower the resistance on the bottom variable resistor. The Voltage won't change, but more current will flow down the bottom path. More current=faster motor
>>8026344
So changing the current to one, would change it on the other motor in the opposite direction so to speak
faster motor a = slower motor b
How would I make these independent?
>>8026349
yeah you have a specific amount of current coming from your power source and it gets split up based on the resistance.
what do you mean by independent?
>>8026360
I want them to be controlled seperately, like 2 cars powered by the same power supply
but so i can choose the power to either of them without affecting the other
>>8026365
MAybe something like this
>>8026288
how large
Could AI solve theoretic mathematical problems
>>8026415
yes
>>8026415
theoretically: yes
in reality: no
the limitations of AI are readily apparent if you simply look at the progress of machine language translation
Is there a compact non-rectifiable set in [math]{\rm I\!R}[/math] other than the fat Cantor set? What about a bounded open non-rectifiable set?
>>8026069
Set <10 equal to 0 and subtract 10 from every value over 10 or just set <10 equal to 10. Or substitute <10 with 5 or an individually randomly generated value 0-10.
If you can somehow approximate a normal distribution based off your values >10, then use that to generate a random value along the normal distribution <10. That's probably the least skewed. Don't forget there should be proportionately more 0's than low values like 1 since you can't have negative values.
Each will results in different degrees of data skewing but just make sure to state what you do as an assumption of your analysis.
>>8026081
Metabolism generates heat constantly. The amount varies with mainly muscle but also other tissue activity. You have a baseline metabolism you have to maintain just to keep your body functioning. Your body generates more heat than it needs to reach 98.6*F because you radiate some of it out through your skin into the environment. If the environment is close to or exactly 98.6*F then just as much heat radiates into your body as leaves. So that extra heat you normally produce heats up your tissue beyond the preferred homeostatic temperature and if we couldn't sweat you would get heat stroke in minutes (Our biochemistry likes to stay well below 104*F).
Sweating is a much faster and efficient way of losing heat than simple convection and IR radiation through the skin. When your body starts detecting an unwanted rise in body temperature you start to sweat in order to avoid overheating, which can set in quickly so it's better not to take chances. Evaporative cooling takes advantage of the high specific heat and volatility of water combined with the likelihood that overheating animals are usually moving relative to the air. You pretty much boil each molecule of water in a drop of sweat one at a time, losing a huge amount of heat in the process.
>>8024650
PCR/ SANGER SEQUENCING NIGGA
I worked as a genetic analyst for a year. Essential you add a few reagents to your sample such as big dye and primers. Then you hand it off to a machine and the machine gives you a read out of placements. Of course you can run into problems because of how C and G bond and the purity of your substance.
>why can't we just change our genes however we like
Analyzing genes takes fucking forever. Like it costs very little sequence but figuring out what they actually do is pretty difficult. One funny out come of the genomic revolution is that we can now sequence an entire genome for less than a thousand but the analysis could cost well over a million. I've always explained it as imagine DNA as computer code. Sure it's easy to "see" the code but if you were to try to figure out what it does without any documentation it'd be pretty rough.
Also you can't just go in willy nilly and change genes. Usually any sort of research in this area is super amounts of trail and error and it takes years to find a gene that you're looking for.
Hello /sci/
I have a kinda stupid question.
If I had a titanium coin, a steel coin, a brass coin, an aluminum coin, and a nickel coin in my pocket and I went out for a walk in a sunny day, which one would be colder when I return to the house?
Would they be at the same temperature?
What about a plastic coin?
>>8026555
Yes. All the same temp if they are in the same temp environment for a long enough time.
The reason why metal feels colder than plastic is that heat transfers faster from you to metals than plastics
https://youtube.com/watch?v=vqDbMEdLiCs
>>8026565
Holy shit so that's why some heatsinks are made of aluminum.
So thermal conductivity is basically like sucking heat right?
So,
They would feel colder in this order?
- Aluminum
- Brass
- Nickel
- Steel
- Titanium
- Plastic
r-right?
In a sunny day it would feel better to carry an aluminum coin because it would feel colder to touch?
Does true random chance exist in the universe?
What's the birth date of probability and combinatorics research area? I plan to become a researcher in these areas but I'm afraid I was born too late. Are they good research areas?
i found a spoopy coincidence related to mind control, i have a question about carrier waves and modulation:
what im doing:
trying to figure how through-wall mind control is done. my best guess is modulation signal via carrier-wave (carrier wave has better through wall properties) and theres multiple patents for this.
coincidence:
- power lines are 60hz; 60hz is "little known about but related to central nervous system activity"
> http://www.bibliotecapleyades.net/ciencia/ciencia_cambio06a.htm
- the mattresses repeat the power line waves
> http://www.europeanbedding.sg/what-sorts-of-electrical-energy-are-flowing-on-your-mattress-a-67.html
- coils are both on the lines and the beds
- coils may be similar to sacred geometry (repeated squares/helix) or mind control patent via square waves
question:
so I'm wondering can a satellite (radio) hit a single transformer or tower; and add a wave-form to the whole grid? how can i use the tower or transformer to add a wave?
are they literally broadcast the fear/obey shit? :)
is assisted suicide illegal because then you can't pay your medical bills ?
Does your brain heat up when you are thinking hard?
>>8026852
I imagine it is illegal because it becomes a nightmare to actually prove things like whether consent really happened, whether the person was competent to render such consent, etc. It's easier to just forbid the practice entirely than to have to sort that shit out every time.
If I fall into a supermassive black hole backwards, facing away from it, would I see the entire future of the universe play out just before crossing the event horizon?
If science can't definitively proove that God does not exist then why not believe? Better safe than sorry right?
>>8026834
this is why england doesnt have sheeple
What's more useful: Computer Science, Mechanical Engineering, or Computer Engineering?
I define useful by: Job opportunity/flexibility, Income, and overall helpfulness
why does nobody talk about eugenics at all? >>>/pol/71919902
>>8026917
> Better safe than sorry right?
Safe ? incase what ?
>>8026917
Because since your first statement is true (where the god of Abraham is concerned, which it is reasonable to suppose is the one god you were referring to), it follows that science also can't prove the existince of this-or-that other god. In other words, any number of gods might be the "true" god, with his/her/xir own special punishments, to the exclusion of the other, presumably false gods. This can be logically extended to every cult and religion that ever existed, and it is even easy to concoct an infinity of variant religions that were never actually practiced by humans - but which have the same property that science cannot prove that their respective, recently-invented gods do not exist (or do exist, for that matter).
Basically, your conclusion makes the same mistake as that of the mathematician Blaise Pascal's wager: you assume that the universe of discourse on this matter is limited to god-of-abraham/not-god-of-abraham, and whatever personal choices you can make. This is clearly false and so Pascal's wager is rejected by serious philosophical inquiry these days as a spurious meme, and the same can be done with your supposition.
This leaves us, honestly speaking, with an infinity of (unpleasant) possibilities, from which one wishes to derive truth. What is special among these possibilities? The peculiar possibility that none of these gods exist. And, that we seem to do better as a civilization when we use the scientific method (I really mean this. We have not merely "made gadgets", but we have also raised quality of life, extended life, and consequently not only made things, /but actually made life more humane/. The sticking point of war aside, modern society is far less violent than primitive society). From here one can make a straightforward moral/aesthetic argument for atheism, which accounts for atheist communist atrocities, which is where the argument can and should terminate. But we'd need more than 2000 characters on a Balinese puppet show.
>>8022778
How the fuck do regular expressions work?
e.g. {a,b}* could that translate into these:
>a
>ab
>bbb
>aaaaaaaaaaabbbb
>>8027282
Theyre patterns....
All those examples fit the pattern.
>>8023289
Easy. You have plenty of time.
If your goal is to be able to solve problems quickly then do problems.
What I do for my courses is I do in-depth readings, make some notes on concepts that are new to me and write on cue cards the equations that are necessary for solving problems.
But the biggest thing for success, is caffeinate up and literally do as many problems as you can in several long sittings.
It's only April, June 15th is far. This is completely doable even if you have zero knowledge on these topics.
>>8027298
Well that's reassuring, But I am studying math and chem at the same time as well. I have absolutely no problem in studying more than 10 hours per day, I just need to know where to study from and what to do and I'll do it.
(I think I'm pretty much fucked on chemistry, I suck at it. As for math just going through axler's pre-calculus real fast and then doing a calculus book)
I own the Y&Freedman university physics book and I don't work for now so I have all day, what do you think?
Should I be worried?
>>8025489
Thanks for the clarification! I wanted to confirm one more question, this time about modular arithmetic.
So I am trying to answer pic related and I think n=22,25,28. My logic is that for 60 div n , n can only be the values 21,22,..,30. While for n mod 3, n can be 1,3,7,..,22,25,28,.. So the only values of n (60 div n) and (n mod 3) have in common is 22,25 and 28.
>>8024380
No, you don't have to put the larger one on top. As long as you do it the same for both. x/y=a/b is the same as y/x=b/a.
Help me integrate this:
[math] \displaystyle \int^{2 \pi}_{0} \frac{d \varphi}{ a^2 \sin^2 \varphi + b^2 \cos^2 \varphi } [/math]
>>8026917
There's a reason "faith" and "religion" are synonymous in the English language.
The point is that you make a logical leap based on faith rather than facts.
>>8027416
WTF
How have you not been kicked out
>>8027676
Community college
>>8027679
You aren't getting anything done with that degree.
Educational institutions hate community college students to begin with for costing them the first two years of tuition.
Unless you're all As and Bs, your degree is essentially worthless.
>t. on the borderline of ruining my academic career at a community college
How am I supposed to approach this? I seriously have no clue, please help.
>>8027639
You can split it up and use trig identities to make it into an integral from 0 to pi/2 to avoid problems with branch cuts.
[eqn]2 \left( \int_0^{\frac{\pi}{2}} \frac{dt}{ a^2 \sin^2t + b^2 \cos^2t } + \int_0^{\frac{\pi}{2}} \frac{dt}{ b^2 \sin^2t + a^2 \cos^2t } \right)[/eqn]
To evaluate just multiply above and below fraction by sec^2(t) and substitute u=tan(t).
A little care has to be taken if you care about complex a and b. I get [math]\left( \frac{1}{b^2} \sqrt{\frac{b^2}{a^2}} + \frac{1}{a^2} \sqrt{\frac{a^2}{b^2}} \right) \pi[/math]. If a and b are real numbers it simplifies to [math]\frac{2 \pi}{|a||b|}[/math].
>>8027864
Thank you very much.
>>8022778
Do quantum particles behave like matter when being observed because they "know" they are being observed or because the method used to observe causes them to behave differently? Does time exists in the quantum field?
how do i solve this for x,y,z?
wolfram spit out pages of garbage
I have a question regarding the meaning of "or" in mathematics. Consider the statement: a=2c or b>3c. Does this mean only one of these properties can only be satisfied at a given instance?
>>8028063
This could have been resolved by a quick google search or opening any math textbook ever, but I'll help out. "P or Q" is true if either of P and Q is true, so a=2,b=0,c=1 and a=0,b=10,c=1 both work.
Consider language L = {ω | ω ∈ {a, b}∗, na(ω) 6= nb(ω)}, where na(ω) and nb(ω) denote the numbers of a and b, respectively, in string ω.
2. (15 points) Prove that L is not a regular language by the pumping lemma.
Anyone know this? It's for a practice exam problem. I know how to prove pumping lemma, but I'm not sure which string I should use to pump.
>>8028497
I posted a thread with my question, didn't realise a thread was up. Anybody know?
>>8028042
combine like terms
>>8027279
But surely investing in one out of a sea of infinite possibilities is better than giving up and choosing nothing.
Or if you're that worried then why not make a spreadsheet of all the different religions out there and just choose the most you can find with relatively compatible belief sets, while simultaneously offering a relatively pleasant afterlife. That way you have the highest chance of a meaningful success.
Why does the universe conform so neatly to our own relatively arbitrary definition of mathematics?
For example take the inverse square law, why should so many things work on an inverse square? What should the universe care what a "square" is? Why not an inverse to the 2.734059 power or something?
Why doesn't the fundamental theorem of algebra fail us sometimes when dealing with complex roots?
Can someone explain the concept of 'significant digits'?
>>8024325
Just a thought, but how about just reversing the direction of thrust, however they're producing it?
>>8028972
I wont judge.
The mechanism of "n" significant digits means you only display the first "n" digits of a number.
You start counting at the first non-zero number, and you also round it if necessary.
Examples:
1.2464092 to 3 sig figs is 1.25
0.0073411 to 4 sig figs is 0.007341
0.90001 to 2 sig figs is 0.90
78365801 to 3 sig figs is 78400000
Is that clear?
>>8028653
Think about what the square function means - its not arbitrary.
>>8028653
> omg lol howcome universe fits so well that the mathematical rules we came up with
It's the other way around buttboy. We make mathematical models based on the laws of physics that govern the universe.
I bet you think it's a giant coincidence that water freezes at 0 degrees and boils at 100 degrees. But its a stupid questions thread so I'll give you a pass.
If there is infinite numbers between 1 and 2, how do you get from 1 to 2?
I'm kind of confused about crystallographic directions. Is [030] supposed to be equivalent to c[010] with a different scalar for instance? My class has no lecture and the book is a bit verbose.
>>8028972
>>8028980
And the purpose of significant figures is to represent the approximate level of uncertainty of a quantity, be it measured or calculated. For instance, if you measure 100 mL of water in a graduated cylinder down to the nearest mL, then add 2.0 mL of ethanol measured to the nearest tenth of a mL, the resulting concentration is 2.0/(100+2.0) = 1.9608%, but the uncertainty of this result is driven (mainly) by the uncertainty of the ethanol measurement, which is only known to two digits. Therefore the best practice is to express this to the nearest second digit as 2.0%, so as not to reflect any false precision and certainty. Also note that it is not simply 2% or 2.000%, because 2.0% indicates that our result is precise to the nearest 0.1% (which it is).
>>8029025
The time it takes you to do so can also be subdivided infinitely. So it's not so strange to advance an infinite amount during an infinite amount of time.
>>8026834
any answer?
>>8028980
>>8029050
Thanks. Your examples and explanation are clear, except:
> uncertainty of this result is driven (mainly) by the uncertainty of the ethanol measurement
Why? The uncertainty of the water measurement (1 ml) is 10x the uncertainty of the ethanol measurement (0.1 ml). So the overall/total/whatever uncertainty should be 'driven by' the former, no?
I'm convinced it's impossible for someone to learn math when they don't notice any problems with much beyond basic algebra... namely myself.
I look at algebra, and calculus, and see how they solve problems, but it seems to me that there really isn't anything else to know. Even the most basic of courses in other fields like set theory or Galois theory just leave me wondering how you can, for example, assume something as outlandish as the ex falso quodlibet law of logic systems is true and say that this actually has any bearing on reality.
Taking even the most basic courses on things like abelian groups just leave me totally puzzled. I think I have Mathematically Abstract and Conceptual Dyscalculia, MACD, totally separate from normal dyscalculia which can't understand basic algebra.
Want to know how bad it is? I've spent the past 12 hours trying to piece together what is trying to be done and why they work onward from 9:30 in this video:
https://www.youtube.com/watch?v=cxNq-hQwvn0 [Embed]
TWELVE hours. Twelve.
Anyone else with this problem? How do I change my perspective on these things?
>>8024882
>people tend to think biology is just memorising the name of things,
it is bra.
usual phys/chem lab-course: he're are all chemicals you are working with - you need to understand what they 'are doing' before you're even allowed to handle anything
usual biology course: Take solution A and mix it with solution B then make a picture of it
What is A? What is B? Why is this happenning or why i am i here? No fucking reason to ask that since your only work as a biologist is to remember the task in the correct order as nobody would expect a biologist to actually know what he is handling
Whats the general element of the U(1) group and how do I prove its Abelian? Am I correct in thinking it should be a matrix?
>>8029164
>general element
i don't know what this is, but it makes me think you just read "for a general element in U(1)" and then skipped to the end of the problem
forgive me if i'm wrong though
i'm in a good mood so i'll try to work it out and explain the mental process
U(1) is, by definition, the group of all 1 by 1 unitary matrices, so yes, if the general element is an element of U(1), it's a matrix
a unitary matrix is a matrix M such that M multiplied by its conjugate transpose is the identity matrix
because a 1x1 matrix only holds 1 element, the conjugate transpose is just the 1x1 matrix containing the complex conjugate of the original element
multiplication in U(1) is just complex multiplication (which is commutative, proving abelian property), so you're looking for the set of complex numbers that when multiplied by their transpose are equal to 1
multiplying a complex number (a,b) by its conjugate is simply (a^2+b^2,0)
so you're looking at all complex numbers (a,b) such that a^2+b^2 = 1
that's the defining equation for a unit circle, so the elements in U(1) are in the unit circle
because when you multiply two unit-length complex numbers, you get another unit-length complex number, the multiplication operation in this group is basically just rotation around a circle
so U(1) is a circle
that's kind of neat actually
this is my first time doing anything higher than calculus btw, i'm literally just plug-n-chug definitions from wikipedia you should have been able to do a least that much
>>8029201
The sheet I'm reading it from says the general element which is probably why I'm confused. Trying to learn this shit with retarded notes is pretty difficult, any good sources other than wikipedia for learning this?
>>8029162
i also said, "while that is partially right"
anyway, what cool things can i do with an oscilloscope?
so i found this incredible article on the tensor product
https://www.dpmms.cam.ac.uk/~wtg10/tensors3.html
the way it builds up to the definition of the tensor product is fantastic
are there any more resources like this that explain in this way why we actually need the abstract pile of shit we're working with, and not just a textbook definition?
i can't imagine that the clusterfuck that is category theory was just developed for fun, and would love to see some some of the history and the questions that led to all of the definitions and stuff.
it really helps me build intuition, but maybe i'm just stupid
I am going crazy here. Is it possible that there are no fucking data about ubiquitin thermodynamic parameters?
I found some equations for unfolding free energy to relate it with pH and the concentration of denaturant, but they are not enough to calculate the unfolding free energy at 7pH, no denaturant, 298k.
>>8029134
bump
>>8029162
>usual biology course: Take solution A and mix it with solution B then make a picture of it
What is A? What is B? Why is this happenning or why i am i here? No fucking reason to ask that since your only work as a biologist is to remember the task in the correct order as nobody would expect a biologist to actually know what he is handling
What the fuck are you on about? Faggots like you need to be called out so that the nonsense you spout is not taken seriously by someone who hasn't formed an opinion on something. There is a reason the phrase "It's just memes" exists on 4chan. You shouldn't comment on something if your only exposure to it is /sci/ memes. Jesus.
>>8028913
Because it's about complex roots. I don't think I get your question.
Does this make any sense?
I want to solve for the series 1 + 2 + 4 + 8...
I take the following steps:
x = 1 + 2 + 4 + 8...
x -1 = 2 + 4 + 8....
x -1 = 2(1 + 2 + 4...)
(x-1)/2 = 1 + 2 + 4...
x = (x-1)/2
2x = x-1
x = -1
It all seems too simple and the answer defies logic.
1+2+4... is infinity, and yet the math shows it as -1.
>>8029450
In this reasoning, you start by assuming that x = 1 + 2 + 4 + 8 + ..., and then you show that x = -1. As a consequence, this (correctly) shows that IF x is the sum of 1 + 2 + 4 + 8 + ..., then x = -1. In other words, it shows that IF such a sum exists, it must equal -1.
What it does not show is that this series has a sum at all, and indeed it does not. Every step in that proof is correct, but it does not show what you think it shows.
>>8022778
What if another highly advanced specie lived on earth before us but they nuked themselves and everything else out of existence two billion years ago, and all other lifeforms evolved from there?
How the hell do I organize this course list, /sci/?
http://ocw.mit.edu/courses/mathematics/
I want to try to teach myself mathematics, at least enough to have a firm grip on the theoretical concepts. My current plan is:
Single Variable Calc => Calc I with Theory => Multivariable Calc => Calc II with Theory => Differential Equations
Then what? Algebras I and II? Number Theory? Analysis? Geometry?
I just want to be able to learn things in the right, progressive order. Please help :,(
>>8029560
The courses in that list look nice at first sight. My recommendations below are based in what seems to be your priorities, which seems to be quite reasonable (analysis first, algebra later and then the rest) My whats and whys
> First pick up with Vector Spaces Algebra (linear Algebra), I think it's part of Algebra I.
Why? Because everything is a vector space. Analysis works with vector spaces and the study of more complicated algebraic structures uses vector spaces as a tool.
> Real analysis and calculus.
Calculus is just applied analysis and you will have the insights of applying the theorems you prove in analysis, such as the mean value theorem or the implicit function theorem. Go over the analysis course and keep pace with calculus at the same time.
> Topology
Topology will clarify questions regarding subsets and continuity. Pick it up when references to topology appear too often in analysis. It's easy and a mind-opener.
> Measure theory (Lebesgue's)
In the context of real analysis, this is the 'advanced' course. You'll expand your understanding in integration and many pieces of the puzzle will be put together after this.
> Fourier analysis
The logical continuation after introducing the Lp spaces with Lebesgue's theory is of course using them.
> Further analysis courses (complex analysis, functional analysis, diff equations)
If you did everything above, I strongly recommend these three for you. Also, everything before isn't strictly necessary, so you may start one of these before finishing all the list above.
I hope this analysis-oriented list helps. If you get tired of analysis, you can do algebraic structures courses, Galois' theory, differential geometry or applied math (statistics, numerical methods...) as you want.
I'm not terrible or amazing at physics/math and I applied to a program in engineering physics, which I heard is very difficult.
How fucked am I? I just really want to know how things work, but hearing about how loads of people drop out makes me afraid.
how to find the sample path of a markov chain with the transition matrix and initial distribution?
How do I into fungi?
whats some good starter books. So far I have found The fifth Kingdom, and "an introduction to fungi".
Where should I go to submit research I've done on something?
>>8029854
They teach you everything you need to know. Passing undergrad is not that hard.
>inb4 some kid starts with some "my school is so hard they put us all in a ring and makes us beat the shit out of each other until only one student is standing and he is the only one who gets to pass the course" superiority bullshit
STEM anons that had a foreign language req what did you take and why?
>>8029829
Thanks man, I really appreciate it
>>8029829
Further questions though:
What about Algebra 2 and the Calc Theories? Are those just a bunch of number crunching classes that don't help further understanding?
What about Number and Set theories? I know I'm getting way over my heAd for this but I wanna know that I'm not missing out on some deep shit.
>>8030067
Took German. Doesn't really matter what language you pick - although if you did like high school French I'd continue that- if your college has a foreign language req then just do whatever mane.
>>8030184
I was just looking for some inspiration because I don't really feel inclined towards any of them.
>>8030180
Why don't you focus on competing one class first, and maybe you'll get some idea of what you can continue with.
>>8029033
What book are you using? Try with Askeland.
>>8028649
Because at this point, the matter ceases to be scientific and becomes a philosophical one. It's not /sci/, but we can get away with considering it here, as this is the stupid questions thread. There are at least three approaches. You could choose to approach religion from an academic philosophical "smart guy" standpoint, adopt mainstream religion and study theology, as you suggested, or your could take the everyday philosophical approach and make simple determinations about what you personally value, why you think xyz, and draw conclusions.
In terms of the latter, one could summarize a choice to believe or not based on "general principles", a phrase I like because it connotes intellectual honesty: "/I don't like that, and I think that that's bullshit. So I'm just plain not going to do that./".
When considering religion, I prefer to blend the latter with the former, ending with a conventional materialist, atheistic outlook. The very pith and stuff of the fedora outlook on the world. Exactly because I value truth and knowledge as categories of human thought over and above most others. I'm not going to spend time on x that /I don't know is true/, when slightly-different permutation x' might be true /and I don't know whether that one is true either/. I am happy to leave it aside for a lifetime.
Or if you're picking one only because you've made an intellectual choice that some hell might exist and you want to minimize your chances of going there, then this too is bogus, and goes back to my general principles: /I don't like that, and I think that that's bullshit. So I'm just plain not going to do that./ I totally reject the idea of ingratiating yourself to unjust god Q to avoid hell P, /even and especially in the case that that is how the universe actually works./ The irony is that this same "argument from inauthentic belief" that Pascal's wager opens up has already been explored and rejected as disingenuous by other fedoras, and probably for like reasons.
>>8030180
> Algebra II looks like more algebraic structures + Galois' theory, go for it.
> I don't think Calc theory it's useful if you're taking analysis, it seems like an hybrid between the pure practical calculus and the more theoretical analysis.
> Number theory: I have never done it, so I can't say. But I think you need some solid basis in Algebra, so pick Algebra first.
> Set theory: Fundamental, but not necessary (the set theory you are gonna need is so easy you can learn it by inertia, without spending additional time). If you want to learn category theory you may need a more rigorous set theory, but I warn you that's harsh.
I've just got a new textbook and it covers ideas I've seen previously, but uses different notation, which has led to a little bit of confusion.
For example, in my first textbook, the acceleration of a projectile has units ms^2, while in the second textbook it's ms^-2.
What's going on?
>repost from /g/
I have to make a key and lock system using an octal number as the password and when the correct key and lock octal is entered then an LED at the end of the circuit lights up. I've done this, but now the second part of the assignment is to add a counter to the circuit that will count the number of failed attempts and then completely shut down the circuit if the number of allowed attempts is passed (until the circuit is reset). We're only allowed to use AND, OR and NOT gates and I can't find any examples/tutorials on the internet. Because we're not allowed to use D flip flops I'm having trouble. I know that the output of the key/lock will be combined with the output of the counter in a final AND gate before the LED. Not asking you to do my assignment for me, but could you please post some links to relevant information. I'm really stuck
Hey /sci/, I just want to verify if the notes I took are correct (Group and Ring Theory)
Let [math]A[/math] be a ring, not necessarily an integral domain, and let [math] a \in A^* [/math], and [math] b \in A \setminus \{ 0 \} [/math].
Does it imply that [math] ab \neq 0 [/math] ? Thanks
>>8028649
How do I find the domain interval on the function
[math]log_2(log_3(log_2(log_3(log_2(x)))))[/math]
>>8030611
figured it out meself mates, in fact it does
>>8030611
Yes. Suppose ab = 0 and multiply by a^{-1} on each side.
Is there any research done online somewhere on why I'm such a whore? I just put my dick in two men and seeded their assholes, which means I'm probably ridden with AIDS now.
>>8022778
is there a way in latex to create a new command if statement, that pretty much says, if there is x amount of vspace left on the page, start this next environment on a new page?
i want to pretty much say if theres only 3 inches left on the page, go to the next page
How can I mathematically prove that 1=1?
>>8031110
I'm not sure you can prove that since it is basically just the definition of equality.
>>8031117
No, not really. For example, let's say I have one apple. And let's also say that my friend has one orange. How can you prove that my one apple is the same amount as his one orange?
To put another way, how can you prove that my "one" is not slightly larger or smaller than his "one"? Since rather than referring to the same quantity twice, or two "one"s are actually referring to two independent quantities that both just happen to be one.
So, how can you prove that every instance of a particular integer will carry the exact same value?
Why isn't wood on the periodic table of the elements?
>>8031110
Just prove that "=" has a symmetric relation.
>>8031160
The term "wood" is actually a brand trademark name. The substance's elemental name is "bismuth" and it is indeed on the table.
>>8031165
Thanks, I learned something new today I guess
>people accept that wave function collapse is caused by the consciousness of the observer
pretty fucking retarded
>>8031169
Blame the media for propagating bullshit. Same with that "people only use 10% of their brain lol"
>>8031170
It's not just the media
The Copenhagen Interpretation is what practically even quantum physics text teaches
>>8031213
That doesn't actually specify consciousness anywhere though, does it? It just specifies "measurement", which seems to be more related to the physical interference with the system by your measuring tools than any effect your consciousness of it has.
Did my lecturer mark my shit wrong or am I crazy?
>The sum of 99.2 and 3.265 should be expressed to 1 decimal place. T/F
Should be false right? Why would you give 4 sig figs when 99.2 is 3 sig figs. Even if I were doing it in my working I would just go full number and have 3 decimal places.
>The significance of a constant systematic error can be minimised by increasing the sample size. T/F
Should also be false shouldn't it? Isn't the whole thing of systematic errors that they are constant, like it says in the question, and no amount of changing sample size is going to change the error.
Just want to check before I ask them about it and they start to think I am as stupid as I am.
>>8031271
First one you're right about, always give your solution expressed in the least amount of sig figs given in the problem
Second one should also be false
When will we replace electronics with spintronics?
>>8031271
you'd be correct about the first question if you were multiplying or dividing those two numbers, but when you're adding or subtracting, the answer should have the same amount of sig figs to the right of the decimal point as the value given with the smallest amount of sig figs given to the right of the decimal point
e.g.
36.789 + 24.6
24.6 only has 1 sig fig to the right of the decimal point, whereas 36.789 has 3 to the right of the decimal point, so answer is rounded off to 1 decimal
36.789 + 24.6 = 61.389
= 61.4
Why does radiation cause cancer?
Hans is standing inside a chamber, if he stands in the centre it does not matter in which direction he walks, after 1 minute of walking he reaches a wall. However Hans is standing a 30 second walking distance south from the center. How long will it take him to reach the wall if he walks east?
>>8031578
52 seconds
>>8029450
To evaluate a series you look at the limit to infinity of the partial sums. Your series doesn't converge and so the best you can say it that it diverges to positive infinity. You start by assuming a limit does exist and so the result you get is nonsense. That said, if you were to follow the same procedure for the series [math]\displaystyle f(x) = \sum_{n=0}^\infty x^n[/math] with [math]|x|<1[/math] you would obtain [math]f(x) = \frac{1}{1-x}[/math]. This expression agrees with the series everywhere it converges but is also defined outside of the original domain (everywhere except x=1) and is analytic making it an analytic continuation of the series. If you must write it as a series it is then [math]\displaystyle f(x) = \lim_{\epsilon \to 1-} \sum_{n=0}^\infty (\epsilon x)^n[/math]. Or that's my understanding at least. The same reasoning can be applied to the zeta function.
>>8031578
30√3 seconds.
>>8031567
From the rules of significant figures. There are two separate rules with sig figs: the rules for addition/subtractions, and the rules for multiplication/division. It's just that you all didn't pay attention in high school physics when they explained the addition/subtraction rule.
>>8031613
I never did physics except some super basic shit in my first year. I am in my third year of a chemistry degree, why is this shit only coming up now?
We have always been told it goes straight to sig figs.
e.g.
367.891 + 24.6
6 sig figs + 3 sig figs
= 392.491
= 392
3 sig figs.
>>8031619
I guess you weren't listening then. Your lack of knowledge does not invalidate the rules set in place before you were born.
>https://en.wikipedia.org/wiki/Significant_figures#Arithmetic
"For quantities created from measured quantities by multiplication and division, the calculated result should have as many significant figures as the measured number with the least number of significant figures. For example,
1.234 × 2.0 = 2.468… ≈ 2.5,
with only two significant figures. The first factor has four significant figures and the second has two significant figures. The factor with the least number of significant figures is the second one with only two, so the final calculated result should also have a total of two significant figures.
For quantities created from measured quantities by addition and subtraction, the last significant decimal place (hundreds, tens, ones, tenths, and so forth) in the calculated result should be the same as the leftmost or largest decimal place of the last significant figure out of all the measured quantities in the terms of the sum. For example,
100.0 + 1.234 = 101.234… ≈ 101.2
with the last significant figure in the tenths place. The first term has its last significant figure in the tenths place and the second term has its last significant figure in the thousandths place. The leftmost of the decimal places of the last significant figure out of all the terms of the sum is the tenths place from the first term, so the calculated result should also have its last significant figure in the tenths place."
I was taught this shit when I was 16, for fuck's sake.
>>8031634
I'm guessing it's the fault of his education system, then, and not his own.
>>8031641
Well his shady recollection of what he was taught 2(?) years ago is not convincing enough to place the blame either way.
I'm a biology major and want to get more knowledgeable in other scientific fields (mainly math, physics and chemistry)
my plan was to get some entry level books and start them through, but should I focus on one of them (my plan was to do math first) or should I do everything at the same time? planning to spend a maximum of 3 hours per day on this since I still have other shit to do
suggestions?
>>8031578
this is just a simple physics problem
i can assume that he is not moving at relativistic speeds, so the galilean group will suffice for space
if he stands at the center and translates along an arbitrary normal for 1 minute, he reaches a boundary
so first we take the abelian group formed by units of time (with basis being 1 minute), and because it is isomorphic to the group formed by units of length, we can define a "time metric" on our space group, which behaves exactly like the 'default' metric, but with codomain equal to the group of time units
we define the boundary to be the set of all vectors of time-length 1 minute, which is a circle whose radius is 1 minute
define south to be the unit vector (0,-1), east to be (1,0), and the center to be (0,0)
hans is standing 30 seconds south of the center
define second to be 1/60 of the generating element in the time group
because, by definition, 30 seconds = 0.5 minutes, we find hans' position to be 0.5*(0,-1) = (0,-0.5)
hans begins moving east, and we want to find how long it takes him to reach the boundary
because in this space, lengths of time are line segments, we wish to find the length of the line segment (called HA) starting at hans' position, and ending at the point of intersection of the boundary and a line parallel to the east vector (called A)
if you recall from rational trigonometry, taking the time segment from point A to the point of intersection of a line at A parallel to the south vector, its length, by axiom of extensionality, is 0.5, and so the length of HA becomes apparent, giving you the square root of 3 over 2 minutes
now change basis to seconds instead of minutes, yielding 30 square roots of 3 along the (1,0) second-vector
>>8031684
Scan your notes or something and post them here.
I gotta relearn calc 1 and 2 as well as physics (kinematics fluids and thermodynamics) and a bit of chemistry for an interview. Where's the best place to refresh that? Does that wolfram alpha app solve problems and show steps?
>>8029294
http://bookzz.org/md5/EB8581E498F8D1927C016BEA4C40C287
lets hope you can find something there
>>8031717
>2012
>not knowing about khan academy
come on, son
there's even commercials on television now
Is there a stability criterion for an electrical circuit in terms of it's impedance? I know that a negative real part means there's gain in the circuit but is there a more specific condition for instability?
>>8031724
I thought it only had high school shit. I completely forgot that was a thing. How does it make money anyway, ads or grants?
If the universe suddenly ceased to exist, would we even notice anything? I imagine you'd just be gone in an instant.
Can normal distributions be applied to measurements that aren't probability-based?
How do you do direct and inverse variations with a and b?
I only know them with x and y: just solve for y, ezpz
but what do you do with a and b? solve for a or solve for b?
If two people stand back to back and walk away from each other at 5mph, how fast is the distance between them increasing? Is it 10mph or 25mph?
>>8031933
10mph
>>8031559
Radiation puts energy into DNA nucleobases with aromatic bonds - nucleobases build TT dimers or get other damages - damages accumulate - repair system fails - random gene important for cell cycle fails - tumor
If radiation dose is high enough it even damages cells directly.
>>8031702
You could just use a^2+b^2=c^2
With a being 30seconds because thats how much he stands south and c being 60seconds thats from the centre to the wall.
Which is the same answer of almost 52 seconds.
>>8025567
Enzymes are a special type of proteins.
>>8026367
R.I.P. MSPaint
does anybody here know the z transform? I'm a bit lost on finding the z transform of (1/2)^n*UnitStep(-n). Any help would be appreciated.
I want to find the kernel to [math] \mathrm{ev}_i : \mathbb{R} [X] \longrightarrow \mathbb{C} [/math] .
I get that an [math]f[/math] element of [math]\mathbb{R} [X] [/math] needs to satisfy [math] f(i)=0 [/math]. What does [math]f[/math] factor to? And what is the kernel? thanks.
another question regarding Group/Ring Theory
I've already figured out that [math] \varphi : \mathbb{C} ^* \longrightarrow \mathbb{C}^* [/math] such that [math] \varphi (a+bi) = \frac{a-bi}{\sqrt{a^2+b^2}} [/math] is a homomorphism (conjugate over norm). What is the image of [math]\varphi[/math]? Calculations get hairy
hey /sci/ how do i work out the probability of the next value being 90 or less in this data frame
101, 92, 97, 82
it has to be expressed a number between 0 and 1
>>8033141
You get the average and standard deviation, and then plug in the z-score of 90.
>>8025536
Use polar co-ordinates and multiply by cis(π/4) which is an anticlockwise rotation of the curve. After this you then convert co-ordinates back to non-polar form.
>>8033145
thanks
Why can't I view LaTeX on here? I just see the text that was made to create it but not the conversion.
>>8033205
Get off mobile.
>>8033212
I'm using laptop...
>be me
>be undergrad
>meeting with random professor in two weeks to talk about working for her as an undergrad researcher.
>no lab experience
>average grades
>basically no academic references
I really want the experience. I know I probably don't deserve it, but is there a way to not blow this meeting?
>>8033213
JavaScript disabled?
Hey fags i need your help regarding conditional probability
is there a relationship between b given a and a given b?
>>8033264
How do you get shit like that set up? What year of your undergrad are you in?
