I need help with the following question please get back A.S.A.P.

Find all values of X in the interval 0 degrees <= x < 360 degrees that satisfy the equation 2sin x - cos 2x = 0.

I'm having extreme difficulty with this problem.


Write cos 2x = cos2x - sin2x and then use the fact that sin2x + cos2x = 1 to write your equation without any cosine functions. What you have is a quadratic equation with sin x as the variable. Use the general quadratic to solve this equation.

Since sin x is between -1 and 1 you will find that one of the roots is not a solution to your problem.

I hope this helps,
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