CUET Preparation Today
Find $\cos \left(-\frac{7 \pi}{2}\right)$ |
$\frac{1}{2}$ 1 -1 0 |
0 |
The concept we use here is :- cos ( - θ ) = cos θ Now, cos ( \(\frac{ - 7π}{2}\) ) = cos ( \(\frac{7π}{2}\) ) = cos ( 4π - \(\frac{π}{2}\) ) = cos ( \(\frac{π}{2}\) ) { \(\frac{π}{2}\) = 90º } = cos90º = 0 |
