



 
Bobby, To solve this equation for x my first thought is to use the multiple angle expression for the cosine function
In your case A = B = x so you get
Thus your equation becomes
This still involves sine functions and cosine functions, but I know that sin^{2}(x) + cos^{2}(x) = 1, or cos^{2}(x) = 1  sin^{2}(x) so the equation can be written
or
Write y = sin(x) and this becomes a quadratic in y. Solve the quadratic for y, write the solutions y_{1} and y_{2} in the form sin(x) = y_{1} and sin(x) = y_{2} and solve for x. Remember that 1 ≤ sin(x) ≤ 1. You didn't give any restrictions on x so make sure you have all the solutions. Harley  


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