SOLUTION: solve sin(x)cos(x)=(-1/2)

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Question 389627: solve sin(x)cos(x)=(-1/2)

Answer by Alan3354(69443) About Me  (Show Source):
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solve sin(x)cos(x)=(-1/2)
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Use the double angle formula sin(2x) = 2sin(x)cos(x)
sin(x)cos(x)=(-1/2)
2sin(x)cos(x)= -1
sin(2x) = -1
2x = 270º
x = 135º (principal value)
x = 135º + n*180º, n = 0,1,2,3...