SOLUTION: Please help me solve this equation: {{{ cosx=sin2x }}}.

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Question 794887: Please help me solve this equation: +cosx=sin2x+.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
[0,2π]
solve this equation: +cosx=sin2x+.
cosx=sin2x
cosx-sin2x=0
cosx-2sinxcosx=0
cosx(1-2sinx)=0
cosx=0
x=π/2, 3π/2
..
1-2sinx=0
2sinx=1
sinx=1/2
x=π/6, 5π/6
..
x=π/6, π/2, 5π/6, 3π/2