Recent content by richyw

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    Estimating Rotational Temperature

    thanks! I think initially I forgot to square the internuclear distance which gave me a really weird result. Good luck with your studying!
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    Estimating Rotational Temperature

    Homework Statement An R-branch of a band of a ^1\Sigma - ^1\Sigma of CO has its maximum intensity at J'=11. The internuclear distance is 1.1 Ǻ. Estimate the rotational temperature. Homework Equations My notes don't even really define what rotational temperature is. They say that the...
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    Use the Fourier transform directly to solve the heat equation

    Homework Statement Use the Fourier transform directly to solve the heat equation with a convection term u_t =ku_{xx} +\mu u_x,\quad −infty<x<\infty,\: u(x,0)=\phi(x), assuming that u is bounded and k > 0. Homework Equations fourier transform inverse Fourier transform convolution thm The...
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    Solve the Dirichlet problem for the heat equation

    so if I can solve the equation with u(x,0)=0 and u(0,t)=u(2\pi,t)=e^{0t} and solve u(x,0)=cos(x) and u(0,t)=u(2\pi,t)=0 and add the solutions together?
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    Solve the Dirichlet problem for the heat equation

    ok I am completely and utterly lost on using the eigenfunction expansion method. to solve this problem. I get the equation. I'm going to type out everything I have done. Keep in mind I have never seen the eigenfunction expansion being used, there are no worked examples in my textbook as far as I...
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    Solve the Dirichlet problem for the heat equation

    Thanks, I did do up to the eigenfunction expansion (and attempted that) before I posted here. Of course I want to do the work, but I was not sure if I was even on the right track!:smile: could you explain to me why I don't have eigenfunction \phi_n(x) =\sin\left( \frac{n x}{2} \right)and...
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    Solve the Dirichlet problem for the heat equation

    yes it's supposed to be a ut I don't know what I have learned about this type of question. I don't think I can use a general formula like I could when I had homogenous BC and a homogenous PDE. There is a chapter in my book which shows how to switch a PDE with time-dependent non-homogenous BC...
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    Solve the Dirichlet problem for the heat equation

    Homework Statement Solve the Dirichlet problem for the heat equation u_y=u_{xx}\quad 0<x<2\pi, \: t>0u(x,0)=\cos xu(0,t)=u(2\pi,t)=e^{-t} Homework Equations The Attempt at a Solution I have no idea what to do here. It seems to me like it's a mix of the solutions we learned. I...
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    Can someone explain this equality to me (complex variables)

    Homework Statement I hate to upload the whole problem, but I am trying to evaluate an indefinite integral, and I can follow the solution until right near the end. The example says that for a point on C_R|e^{-3z}|=e^{-3y}\leq 1. I don't understand how they can say this. Below is the question...
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    Need help finding a Laurent Series

    is this correct? for 2 < |x-1|< ∞ I got \sum^\infty_{n=0}\frac{2^n(-1)^n}{(z-1)^{n+2}} and for 0 <|z| < 1 I got \sum^\infty_{n=0}-z^{2n}
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    Need help finding a Laurent Series

    so just f(z)=\sum_{n=0}^{\infty}\frac{(-1)^{n}(z-1)^{n-1}}{2^{n+1}},\: |z-1|<2
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    Need help finding a Laurent Series

    i'm still quite confused. I don't really remember from calculus how to get series expansions that aren't around z=0. I tried \frac{1}{2}\sum_{n=0}^{\infty}(-1)^n\left(\frac{z-1}{2}\right)^n=\sum_{n=0}^{\infty}\frac{(-1)^n(z-1)^n}{2^{n+1}}
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    Need help finding a Laurent Series

    Homework Statement Let f(z) = \frac{1}{z^2-1}. Find Laurent Series valid for the following regions. • 0<|z−1|<2 • 2<|z−1|<∞ • 0<|z|<1 Homework Equations \frac{1}{1-z}=\sum^{\infty}_{n=0}z^n,\: |z|<1 f(z)=\sum^{\infty}_{n=0}a_n(z-z_0)^n+\sum^{\infty}_{n=1}b_n(z-z_0)^{-n} The Attempt at a...
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    Leibniz rule for differentiating an integral w.r.t a parameter

    ok. I see where I went wrong with the chain rule now, I had to write the chain rule in leibniz notation (with ANOTHER dummy variable) and now I think I have the answer. Thanks a lot for your help.It seems so easy now. Although I guess it's always easy once you have figured it out haha.
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    Leibniz rule for differentiating an integral w.r.t a parameter

    wait. am I messing up the chain rule here?
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