Question 691911
Solve the equation for exact solutions over the interval (0 degrees, 360 degrees). Give all solutions. 
4 cos2theta = 8 sin-theta cos-theta
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Use x for theta
4 cos2x = 8 sinx cosx
divide by 4
cos2x =2 sinx cosx
cos2x =sin2x
divide both sides by cos2x
sin2x/cos2x=1
tan2x=1
2x=45º, 225º (in quadrants I and III where tan>0)
x=22.5º, 112.5º