Question

Find two angles that satisfy the equation
Cos(2x-38)=sin(4x-66)

Answer 1

59°, 239°

Explanation:

cos(2x − 38) = sin(4x − 66)

Use phase shift.

sin(2x − 38 + 90) = sin(4x − 66)

The angles are equal, or a multiple of 360° apart.

2x − 38 + 90 = 4x − 66 + 360k

Solve for x.

118 − 360k = 2x

x = 59 − 180k

If k = 0, x = 59.

If k = -1, x = 239.