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ans10.tex
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\begin{Solution}{10.1.a}
$\ds \frac{\pi}{2\sqrt{5}}$
\end{Solution}
\begin{Solution}{10.1.b}
0 ; \textbf{Hint}
\[I = \int_0^{2\pi}{\cos \theta \over 3+\sin\theta} d\theta = Real part of \int_0^{2\pi}{\frac{e^{i\theta}}{3+\sin\theta}} d\theta \]
\end{Solution}
\begin{Solution}{10.1.c}
0
\end{Solution}
\begin{Solution}{10.1.d}
$\frac{2\pi}{\sqrt{3}}$
\end{Solution}
\begin{Solution}{10.1.e}
$\frac{\pi}{12}$
\end{Solution}
\begin{Solution}{10.1.f}
Let
\begin{align*}
I &=\int_0^{2\pi} e^{\cos \theta}[\cos(\sin \theta - n \theta+ i\sin(\sin \theta - n \theta)]d\theta \\
&= \int_0^{2\pi}e^{e^{i\theta}}e^{-in\theta}
\end{align*}
Put $z=e^{i\theta}$,
\[I = \int_C \frac{e^z}{iz^{n+1}}dz\]
Now by residue theorem,
\[I = \frac{2\pi}{n!}\]
Now compare real parts to obtain
\[\int_0^{2\pi} e^{\cos \theta}[\cos(\sin \theta - n \theta)]d\theta = \frac{2\pi}{n!}\]
\end{Solution}
\begin{Solution}{10.1.a}
$\frac{\pi e^{-m}}{2}$
\end{Solution}
\begin{Solution}{10.1.b}
$\pi \log 2$
\end{Solution}
\begin{Solution}{10.1.c}
$\frac{3\pi}{16}$
\end{Solution}
\begin{Solution}{10.1.d}
$\frac{\pi}{3}$
\end{Solution}