Question 183068
(cos(x) - 1) sin(x) = 0
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You are given the factors.  One of them must be zero since the product is zero.
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cos(x)-1 = 0 or sin(x) = 0

cos(x) = 1 or sin(x) = 0

x = pi/2 or (3/2)pi  or x = 0 or pi
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Cheers,
Stan H.