Question

Cos(-180").tan 8.cos 690 sin (8-180) cos² (6-90) (5)​

Answer 1

cos(-180°) = -1

tan 8° = 0.1425

cos 690° = 0

sin (8-180°) = - sin 172° = - 0.9997

cos² (6-90°) = cos(-84°) = 0.4997

Therefore, the answer to the expression is -0.4997.