SOLUTION: help me solve this equation cosx=2sinx.

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Question 832313: help me solve this equation cosx=2sinx.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
cos%28x%29=2%2Asin%28x%29
Square both sides,
cos%5E2%28x%29=4sin%5E2%28x%29
You know that,
cos%5E2%28x%29%2Bsin%5E2%28x%29=1
cos%5E2%28x%29=1-sin%5E2%28x%29
Substitute,
1-sin%5E2%28x%29=4sin%5E2%28x%29
5sin%5E2%28x%29=1
sin%5E2%28x%29=1%2F5
sin%28x%29=1%2Fsqrt%285%29=sqrt%285%29%2F5
Two solutions,
x=26.6 degrees and x=153.4 degrees