Question

Prove: cos(3x)=sin(2x)

Answer 1

Explanation:

Step-by-step explanation:

By taking ( x = 18°)

L.H.S

cos(3x)=sin(2x)

cos(3x) = cos( 3X18°)= cos (54°)

= cos[ 90° - (2x18°)] ∵[ 90°- (2x18°) = 54°]

= ∴ sin ( 2x18°)

As (x = 18°)

= sin (2x) = R.H.S