Question

cos(pi/2 +x) =-sin x in graph​

Answer 1

Step-by-step explanation:

To prove that : cos (pi/2 + x) = -sin x

LHS = cos (pi/2 + x)

= cos 90 cos x - sin 90 sin x

= 0*cos x - 1*sin x

= - sin x, = RHS. Proved.