Author Topic: HA 6, problem 3c (sections 4.1 and 4.2)  (Read 148 times)

Shaghayegh A

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HA 6, problem 3c (sections 4.1 and 4.2)
« on: November 14, 2016, 02:09:32 PM »
http://www.math.toronto.edu/courses/apm346h1/20169/PDE-textbook/Chapter4/S4.2.P.html#mjx-eqn-a

For 3c: I assume that M(y) and N(y) are two arbitrary eigenfunctions with the same eigenvalues $\omega$. Then, M and N satisfy
$$Y^{(4)} (y)=\omega^4 Y(y) \\
Y(-L)=Y_y (-L)=0 \\
Y(L)=Y_y(L)=0
$$ where I've switched coordinate systems so that $y=x-l/2=x-L$. I want to prove
$$\int_{-L}^{L} M(y) N(y) dy=0$$ but I'm not sure how to do that. Any advise?
Thank you

Victor Ivrii

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Re: HA 6, problem 3c (sections 4.1 and 4.2)
« Reply #1 on: November 15, 2016, 07:01:18 AM »
Different eigenvalues. For the same eigenvalue it will be plain wrong