### Author Topic: Lecture 12 Eqn 9 Question  (Read 9810 times)

#### Ian Kivlichan

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##### Lecture 12 Eqn 9 Question
« on: October 24, 2012, 01:59:26 AM »
Hi all,

Just to clarify - should equation 9 in the notes for lecture 12 (http://www.math.toronto.edu/courses/apm346h1/20129/L12.html#mjx-eqn-eq-9) read

$\lambda_n = - n^2 \pi^2 / l^2$ ?

Cheers,

Ian

#### Victor Ivrii

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##### Re: Lecture 12 Eqn 9 Question
« Reply #1 on: October 24, 2012, 02:33:26 AM »
Hi all,

Just to clarify - should equation 9 in the notes for lecture 12 (http://www.math.toronto.edu/courses/apm346h1/20129/L12.html#mjx-eqn-eq-9) read

$\lambda_n = - n^2 \pi^2 / l^2$ ?

Cheers,

Ian

Yes,  there was an error: correct: $\lambda_n = n^2 \pi^2 / l^2$ and also unnumbered equation above (7) should be
\begin{equation*}
\frac{ T''(t)}{T(t)}=-c^2\lambda,\qquad \frac{ X''(x)}{X(x)}={\color{red}{-}}\lambda
\end{equation*}

PS. You are the first person who placed the link!