SOLUTION: Please help me with this question and show all steps if possible thank you! {{{3 cos2x+sinx-1=0}}}

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Question 312176: Please help me with this question and show all steps if possible thank you!
3+cos2x%2Bsinx-1=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
cos%282x%29=1-2%2A%28sin%28x%29%29%5E2=1-2S%5E2
3cos%282x%29=3-6S%5E2
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3%2Acos2x%2Bsinx-1=3-6S%5E2%2BS-1=0
-6S%5E2%2BS%2B2=0
6S%5E2-S-2=0
%283S%2B2%29%282S-1%29=0
Two solutions:
3S-2=0
3S=2
S=2%2F3
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2S%2B1=0
2S=-1
S=-1%2F2
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The angles whose sin%28A%29=2%2F3 are 41.8 and 138.2.
The angles whose sin%28A%29=-1%2F2 are 210 and 330.