Solve each of the following equations for all solutions on [0, 2𝜋). Find exact answers when possible, otherwise round to 3 decimal places.

Question

Solve each of the following equations for all solutions on [0, 2𝜋). Find exact answers when possible, otherwise round to 3 decimal places.

a. cos(6𝑥) = cos (3𝑥)

Answer 1

cos (2(3x)) = cos (3x)

2 cos² (3x) - 1 = cos (3x)

2 cos² (3x) - cos (3x) - 1 = 0

Cn you factor, solve for cos 3x, and answer?