A body oscillates with S.H.M according to the equation $\text{x=5cos}\left[\text{2πt+}\frac{\text{π}}{\text{4}}\right]$ metre its instantaneous displacement at t=1 sec is

Given  $\text{x=5cos}\left[\text{2πt+}\frac{\text{π}}{\text{4}}\right]$ where x is a displacement, t is time
=>$\text{x=5cos}\left[2\text{π+π}/4\right]$ at t=1 second
=> $\text{x=5cos}\pi \text{/4}$     as $\left[\cos \left({360}^{\circ }+\theta \right)\text{=cosθ}\right]$  

=>x=5($\frac{1}{\sqrt{2}}$) meter