Browse Questions

# Which one is not periodic

$\begin{array}{1 1}(a)\;\mid \sin 3x\mid+\sin^2x&(b)\;\cos\sqrt x+\cos^2x\\(c)\;\cos 4x+\tan^2x&(d)\;\cos 2x+\sin x\end{array}$

$\cos \sqrt x$ is non periodic.
$\therefore \cos\sqrt x+\cos^2x$ cannot be periodic.