Archived threads in /sci/ - Science & Math - 301. page
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Trying to teach myself calculus. Explain to me why I can't find the area under this hyperbola, length of the thing, what not, using the perpendiculars that I spent 5 hours in Desmos doing addition of 1/sqrt(2) and 4/sqrt(5) and a bunch of other shit.
>>7941695
because you'll be approximating the segments of the curve as straight lines?
>>7941698
Then what is this meme staircase method I keep seeing? Is that only for repeating series? Define things, please?
>>7941695
what's the curve's ecuation?
All you hear in undergrad is
>DON'T EAT OR DRINK IN THE LAB
>DON'T EAT OR DRINK IN THE LAB
>DON'T EAT OR DRINK IN THE LAB
At what level can I have a bottle of water or a cup of tea in the lab? What's wrong with having a snack while I'm babysitting some boring reflux reaction?
because if you get to eat/drink in the lab others will too and its going to snowball into an accident
>>7941653
>actually bringing food or drink into the lab
It's like you're asking to get poisoned. God knows what someone might slip into your drink or what might end up in your drink by accident.
I seriously can't believe there are people as stupid as you on attending university right now.
Are you a flawless, perfect God who never makes a mistake, ever?
No? Then don't eat or drink in a lab. You're going to fuck up one day when you're tired or distracted and spill a drop of toxin into your tea or get a drop of supervirus on your BLT and fucking die
w2c Rudin's or Tao's textbook on Analysis? Fucking hell shit can be expensive
pic obviously unrelated
>>7941604
Just download the books.
>Rudin
Literally pointless to use.
>Taos
Nobody has ever heard of it.
Both belong in the trash.
Yeah, no way I'm paying 20 bucks for a brand new edition!
So I'm reading through Zakon's Basic Concepts of Mathematics, and during the set theory introduction, we're asked to prove the basic operations of sets.
I'm coming directly from euclidean geometry, and I feel like this book does not present its definitions and axioms clearly enough. For example I have found out these proofs rely on basic laws of logic, e.g. the proof for the commutative law for sets is just the commutative law for logic, under a new name. That feels really silly. Is there a proof for this law in logic, or is it taken as an axiom?
I believe most of those logical laws are proven by writing out the truth tables for the statements to be compared and if they are identical, that indicates equality. For example, writing the tables for A^(B || C) and (A^B) || (A^C) would yield the same thing.
>>7941218
So the truth table for A v B would be:
A B AvB
T T T
T F T
F T T
F F T
whilst for BvA it would be
A B BvA
T T T
T F T
F T T
F F F
and this implies equality?
>>7941286
Sorry, last one there should be F for the the first table.
say somebody hasn't taken maths in a few years and they have 6 weeks to study until they start calc 1. what are the essentials that they should review?
buimo
>>7941059
>6 weeks to study
>calc 1
You litearlly have to do nothing.
>>7941102
I wanna be prepared anonymoose
Physics majors,
I understand that gravity deforms the spacetime through which it acts. In other words its presence changes the domain of its own propagation. What sort of mathematics do you guys use to represent that sort of thing where the solution to the problem changes the domain of the problem itself?
I'm trying to gain a more intuitive understanding of a solid mechanics problem in engineering, where stresses acting through a solid body deform the shape of the solid, further changing how the stresses act through the body. Over here we use some wonky PDE...
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>>7940124
>What sort of mathematics do you guys use to represent that sort of thing where the solution to the problem changes the domain of the problem itself?
pde
>>7940124
>I understand that gravity deforms the spacetime through which it acts. In other words its presence changes the domain of its own propagation. What sort of mathematics do you guys use to represent that sort of thing where the solution to the problem changes the domain of the problem itself?
The wording of your question is weird and not really true. Gravity IS the deformation of spacetime.
To represent this we use what we always use. The principle of least action, which uses the...
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>>7940124
In general relativity spacetime is described by differential geometry - specifically (pseudo-)Riemannian geometry. Differential geometry describes geometric spaces called differential manifolds, such as smooth curves and surfaces, and their higher dimensional generalisations. The specific details of distances and angles in this space are given by a metric tensor on the space, from which properties like the distance between points or the curvature can be derived - this is Riemannian geometry.
The mathematics of Riemannian...
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Hello, /sci/. I would like to create a Facebook page dedicated to non-fiction books ratings. I need to gather a team of people interested in science who have some free time for reading and writing the ratings. Is anybody interested I. That kind of stuff?
*in that
>>7939981
How much will you pay?
>>7940029
Ahaha. I will pay you nothing. It just would be joyful for you to gain your knowledge and share it with other people.
The Airbus A380, the world's largest passenger airline. Name your favorite engineering marvel anon.
>>7939852
muh dick
![Falkirk-WheelL_tcm4-570249[1].jpg](https://i.imgur.com/TWuHqWO.jpg "Falkirk-WheelL_tcm4-570249[1].jpg")
Falkirk Wheel.
https://www.youtube.com/watch?v=_tBH9SE-Kw8
>>7939852
Just saw a documentary about hypercars. Pretty sexy senpai.
What will happen to us when the magnetic fields flip? Will there be any danger?
Do we know exactly when the next time it'll flip is?
just be thankful we still have a magnetic field
Magnet based compasses will be messed up. Animal migrating birds might have trouble, assuming they actually use it.
But it's not like it's going to happen overnight. It'll probably take years to complete. Maybe even decades.
>>7939756
I think its any time from now to the next 200,000 years. That bein said it doesn't just flip at one moment and it takes thousands of years to flip and it flips in zones first meaning there's not a period without a field.
Stupid Questions Thread
>How many joules of heat are needed to change 50.0 grams of ice at -15.0 degrees celsius to steam at 120.0 degrees celsius?
I fucking missed this and now I'm lost. I'm supposed to use these equations multiple times or something:
[math]q=mC\DeltaT[/math]
[math]q=n\Delta H_{fusion or vapor}[/math]
What's the difference between these equations and what do I actually do with them?
>>7930606
fucked up the equation, it's
[math]q=mC \Delta T[/math]
>>7930606
energy needed to raise heat up to 120 degrees.
plus energy needed to change ice to vapour.
state changes cost energy.
increasing the temperature costs energy.
so you need to use both.
my chem is a bit rusty, but its 4.2x135 + whatever the vapour value is for ice.
sorry. high school chem was like 5 years ago.
Should I take all mineral supplements at once or at separate times of the day?
Will they compete for absorption if taken at once?
I'm currently using magnesium, zinc, copper, manganese, selenium and iodine. What should I add?
>get put into two prerequisite 100-level courses (maths and physics) that I've already learned everything for because the NCEA examination system is bullshit and screws over people randomly
>university is completely unsympathetic even though it makes my degree a year longer and they acknowledge that I'm learning nothing, and they say "anon, if you know everything you should be able to get an A easily!"
>I actually end up being handicapped because I forgot how to do things...
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>>7939224
I had the opposite problem:
>Start a masters
>Don't meet the pre-requisites for 2/3 of my electives.
>Boss the shit out of all of them, except algebraic geometry.
>Algebraic geometry is hard.
I've no idea how you survive your problem, I just put in a shit load of extra effort.
>>7939229
Algebraic geometry reminds me of how shitty the rest of my course is.
So this trimester I'm taking:
MATH 141 (Calculus basics, already learned but abstracted from what I know)
PHYS 131 (Various physics, in the same form that I already learned so I could do last year's final examination with twice the pass mark easily)
MATH 151 (Really complicated algebra stuff, the lecturer knows his stuff but is incompetent as a teacher so I'm completely lost, I think it's algebraic geometry?)
COMP...
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These easy As work themselves out when you go to apply for internships with 4.0 gpa. They work out when it's year 4 and physics 9999 is kicking your ass.
Regards,
CC transfer who got thrown into the gpa killer classes his first semester
Do you think the universe is finite or infinite?
I think the universe is finite because if it were infinite, there would be infinite copies of me, infinite copies of earth, and infinite copies of the observable universe, as well as other things not in our observable universe and then some.
I believe that the universe is so large that it is irrelevant whether or not it is infinite.
>>7938906
Look up in the sky at night... If any part of they sky is black then you have your answer
>>7938906
I'd hope the universe is infinite so there's a version of you that's a little smarter.
Michio Kaku is way better than him
>>7938764
because he knows how to get attention from plebs
idk why people cant figure this out
>>7938764
because kaku is a gook and american children find a happy black scientist relatable
>>7938764
Kaku is worse than NDT
The most disturbing thing about this image isn't the fact that squares "A" and "B" are the same color, it is the fact that the squares in the back are in fact larger than the squares in the front.
wow such disturb many illusion
>>7938551
Illusions like this work on me at first glance, but go away once if I unfocus my eyes. Anyone else get this?
/sci/, will you ever solve a 300 year old unsolved math problem?
http://www.npr.org/sections/thetwo-way/2016/03/17/470786922/professor-who-solved-fermat-s-last-theorem-wins-math-s-abel-prize
Modularity theorem is some cool shit senpai
He made an arithmetic mistake on page 173
>>7938421
>/sci/, will you ever solve a 300 year old unsolved math problem?
It was solved 300 years ago but the proof was not published.
