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Write the number of values of x in [0, 2 π] that satisfy the equation sin2x - cos x = \(\frac{1}4\).

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1 - cos2x - cos x = 0.25 

cos x2x + cos x - 0.75 = 0 

Solving the quadratic equation we get 

cos x = 0.5 

cos x = cos 60° 

x = 2nπ ± \(\frac{π}3\)

x = 60° when n = 0 

And x = 300° when n =1

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