Archived threads in /sci/ - Science & Math - 455. page
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Need some help with this. I know I can replace z4 with exp(4ix) which gives cos(4x)+isin(4x).
The most I am able to figure out is maybe replace z4 with the cos/sin, but how I don't know how to move on.
Many Thanks.
Let z = a + i b
[eqn] \frac{1}{1 - (a + ib)^4} = \frac{1}{1 - (a + ib)^4} \frac{1 - (a - ib)^4}{1 - (a - ib)^4} = \ldots [/eqn]
You should be able to do the rest.
[eqn] z^4 = e^{i4x} [/eqn]
[eqn] \frac{1}{1 - z^4} = \frac{1}{1 - e^{i4x}} \frac{1 - e^{-i4x}}{1 - e^{-i4x}} = \frac{1 - \cos(4x) + i \sin(4x)}{2 - 2 \cos(4x)} [/eqn]
[eqn] \Re \left( \frac{1}{1 - z^4} \right) = \frac{1}{2} [/eqn]
>>7783887
Since [math]|z|=1, {\bar z}=1/z.[/math] Let [math] w=1/(1-z^4).[/math] Then [math] Re(w)=(w+{\bar w})/2=(1/(1-z^4)+1/(1-1/z^4))/2 = 1/2. [/math]
What's this element called, /sci/?
>>7783885
Memerium
>>7783885
al-yoo-mini-um
>>7783885
Aluminium.
See that extra 'I' there, Americans? It's not 'Al-oo-minum', it's 'Al-yoo-minium.' Retards.
Solve this probability distribution question my head hurts post work
>>7783867
you got 10 minutes sci/ go
>>7783867
>>/hm/
is the place for homework
they usually answer pretty fast
>>7783870
Oh thank you I'm new to 4chan
I don't know how to feel about my maths teacher, /sci/. I feel like he's actually holding me back more than helping me. He's the 'funny guy' type teacher, and while he genuinely is funny, I think he isn't doing nearly enough work. I only have about six months to my exams, like.
He gets into slagging matches with students a lot, and he doesn't get enough maths done. My maths skills are poor enough as it is. When he's actually doing maths he's quite good at explaining it, but he laughs and jokes too much.
I don't...
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>>7783839
Why on earth do you need your maths teachers help? Just do everything yourself and use the internet. High school math isn't difficult.
>>7783847
I still need his help for stuff, anon. Sometimes the book doesn't explain a concept well enough, or else I get stuck on a past exam paper question.
I'm getting really sick of the 'laugh joke' thing. I put on a front that I'm enjoying it (though I do genuinely laugh once in awhile), but I'm too nervous/scared to say anything.
I don't know what to do.
>>7783856
I N T E R N E T
there is no maths topic/concept up to the standard first 2 years of grad school that can't be looked up on the internet
Smartest man alive?
>>7783785
Yes. https://www.youtube.com/watch?v=k2T45r5G3kA
>>7783785
Def smarter than /sci/ desu senpai
>>7783808
that guy is kill already.
What happens if an electric eel swims into a pipe of iron and discharge the electricity? Will it create a magnetic field? Microwaves?
Eels are cool.
electrocytes...
>>7783738
>Will it create a magnetic field?
[math]\nabla \times \vec{B} = \mu_0 \epsilon_0 \frac{d\vec{E}}{dt}[/math] for source-free Maxwell, so yes.
>Microwaves?
Depends on the frequency of the discharge.
Tell me about the rainman hypothesis
>>7783735
Repeat after me: Rie-mann
benus
I'm trying to find some data for the IQ of STEM students/graduates. Preferably engineering.
I can only find averages. I want to see all the data.
>>7783711
I saw some data like this while I was at mit, email the stats dept and they will get it to you, probably
>>7783721
Interesting. For what subject? Can you remember some of the outliers (both low and high)? I'm very interested in seeing the outliers. It will greatly satisfy my autism.
Is there any reason why we use rockets instead of airplanes with a liquid oxygen storage to get to space?
>>7783708
Building a SSTO Spaceplane is absurdly difficult and the development costs are more than anyone has cared to pay.
stay tuned my friend :^) NASA basically confirmed the working mechanisms of the EM drive which allows us to travel to Mars in 17 minutes with multi-dimensional wormholes that are fueled by Qualia consciousness gems.
tl dr : Rocket fuel is the most efficient and feasible way to get a fuckton of stuff up to space.
>>7783713
Why not to use airplanes with rocket propulsion? Wouldn't the lift reduce fuel expenses?
We are working with uncertainty principles in my chemistry class and I have no idea how to go about answering this question.
Is there a formula that I can use and can someone point me in the right direction?
The question is:
If photons of green light (wavelength=530 nm) are used to locate the position of the basketball (thrown with a velocity of 30 m/s) with precision of one wavelength of the green light, what would be minimum spread in the speed of the baseball?
You need to use the following equations:
[math] E = \frac{{hc}}{\lambda }[/math]
[math] E = m{c^2} [/math]
[math] p = mv [/math]
[math] \Delta x\Delta p \geqslant \frac{\hbar }{2} [/math]
Hey, /sci/. I know this may be geared towards /adv/ but I dont want to go to that depressing faggot board. Is this too full of a schedule? I need all these classes to be completed because a Berkeley transfer is planned.
Discrete Math
Differential Eq.
Assembly lang.
Data structures
Calc III
Physics III
I'd appreciate any serious responses. I do go to SDSU where Ive noticed that curriculum is far easier than it should be and Ive gotten straight A's, but these classes could be different. Thanks in advance guys
>>7783565
Nah dude you got this.
>>7783565
Pretty heavy schedule, but definitely doable if you focus.
>>7783565
>is this hard???
I don't know what you're expecting to hear. It definitely depends on you, bro. Are you willing to put in the effort required in these classes?
You can always make it feel softer if you study some of it right now so you get with the intuition in place. Try http://ocw.mit.edu/courses/ocw-scholar/
Hi /sci/
i need some books or information sources o energy configurations within atoms,like how the electrons move, how you can see what element something is from its light spectrum. and also about the wave/particle duality.
i cant really find anything that i can use online,
and i cant afford to buy any books.
can /ci/ help me?
fuck you guys :(
>>7784779
>and i cant afford to buy any books.
bookzz.org
>id elements by spectra
Atomic absorption spectroscopy or atomic emission spectroscopy
>>7783539
Here you go, everything you could ever want to know about the behavior of electrons and photons.
[math] \int {\mathcal{D}\psi \mathcal{D}{A_\mu }} \exp \left( {i\int {{d^4}x\left[ {\bar \psi \left( {i\not D - m} \right)\psi - \frac{1}{4}{F_{\mu \nu }}{F^{\mu \nu }}} \right]} } \right) [/math]
Please explain enantiomers to a retard. I don't get it, and I've read the definitions everywhere - in my textbook, on Wikipedia, and on various chemistry sites.
Shove that stupid frog up your ass
Mirror image, compare right and left hand.
Happens when a carbon binds four different groups. If two of these groups are swapped, a mirror image is formed.
If you have a chiral carbon (a carbon atom bonded to four unique substituents), placing that compound "infront of a mirror" will give it's enantiomer. Your right hand is the enantiomer of your left hand. A good check for this is that no matter what you do, you cannot get the original connectivity of the enantiomer without breaking bonds.
Is happiness the most important thing to humanity?
having a big dick is
Who is the boomer consumer?
>>7783477
fuck off to /his/terectomy
WTF is that?
>>7783439
Your mom
