$\Longrightarrow x=2 \cos \omega t=2 \sin \left(\omega t+\frac{\pi}{2}\right) \quad\left[\sin C-\sin D=2 \cos \left(\frac{C+D}{2}\right) \sin \left(\frac{C-D}{2}\right)\right]$
On comparing this with equation of $S H M: x=A \sin (\omega t+\phi)$
$\Longrightarrow A=2$ $\omega(\text { Angular frequency })$
$\Longrightarrow T=\frac{2 \pi}{\omega}$

