Question

Evaluate $\cos {90}^{\circ }\sin {\theta }^{\circ }-\sin {\theta }^{\circ }\cos {90}^{\circ }$

Answer 1

We have,

$\cos {90}^0\sin \theta -\sin \theta \cos {90}^0$

Since, $\cos {90}^0=0$

Therefore,

$=0\times \sin \theta -\sin \theta \times 0$

$=0-0$

$=0$

Hence, this is the answer.