Question 924585
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Hi,
sin x(sin x + 1) = 0 
sin^2 x + sinx = 0
sin^2x = - sinx
sinx = -1
....
4 cos^2 x - 1 = 0
cos^2 x = 1/4
cosx  = ± 1/2
....
refer to (cosx, sinx) Summary Unit Circle for corresponding x-values
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