SOLUTION: verify {{{red(cos(pi-x))+blue(sin(pi/2+x))=0}}}

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Question 296866: verify red%28cos%28pi-x%29%29%2Bblue%28sin%28pi%2F2%2Bx%29%29=0
Answer by Edwin McCravy(20065) About Me  (Show Source):
You can put this solution on YOUR website!
Use the double angle formulas which are


sin%28alpha-beta%29=sin%28alpha%29%2Acos%28beta%29-cos%28alpha%29%2Asin%28beta%29
cos%28alpha%2Bbeta%29=cos%28alpha%29%2Acos%28beta%29-sin%28alpha%29%2Asin%28beta%29
red%28cos%28alpha-beta%29=cos%28alpha%29%2Acos%28beta%29%2Bsin%28alpha%29%2Asin%28beta%29%29

You'll need the red one and the blue one.
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red%28cos%28pi-x%29%29%2Bblue%28sin%28pi%2F2%2Bx%29%29=0



red%28-1%2Acos%28x%29%2B0%2Asin%28x%29%29%2Bblue%281%2Acos%28x%29%2B0%2Asin%28x%29%29=0

red%28-cos%28x%29%29%2Bblue%28cos%28x%29%29=0

0=0

Edwin