Browse Questions

# $\int \limits_{-\pi}^{\pi} (\cos px - \sin q x)^2 dx$ where $p \;\&\; q$ are whole number. Find its value.

$(A)\;0 \\ (B)\;- \pi \\ (C)\;\pi \\ (D)\;2 \pi$

$\int \limits_{\pi}^{\pi} \cos^2 px+ \sin ^2 qx -2 \cos px \sin qx$
$\int \limits_{-z}^{z} \cos ^2 px +\sin ^2 qx dx$
=>$\int \limits_{-\pi}^{\pi} dx$
=>$\bigg[ x \bigg]_{-\pi}^{\pi}$
=> $\pi+ \pi =2 \pi$