Here I have a trigonometric equation, where a, A, b, and B are constants. This equation needs to be solved for x.

0 = a*cos(Ax)+b*cos(Bx)

If the second equation below could be solved for x, that would also solve the problem. Solving one will lead to a solution for the other.

I will use different constants than above to avoid confusion.

G*x = arccos(H*cos(x))