Question 1008266
 Sin^2x+cosx=1
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1-cos^2(x) + cos(x) = 1
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cos^2(x) - cos(x) = 0
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cos(x)(cos(x)-1)) = 0
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cos(x) = 0 or cos(x) = 1
x = pi/2 or (3/2)pi or pi/2
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Cheers,
Stan H.
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