Solve the following equation for all solutions: cos(5x)cos(3x)-sin(5x)sin(3x)=√3/2. I know the formula to use would be cos(A+B), but I'm just not confident in my ability to solve it correctly.

Answer 1

cos(5x)cos(3x)-sin(5x)sin(3x)=√3/2
cos(5x+3x) = √3/2
8x = ±π/6 + 2kπ
x = ±π/48 + kπ/4