SOLUTION: Solve sin3x+sinx=cosx for 0<=x<=2pi

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Question 1012405: Solve sin3x+sinx=cosx for 0<=x<=2pi
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
sin%283x%29%2Bsin%28x%29%22%22=%22%22cos%28x%29

sin%282x%2Bx%29%2Bsin%282x-x%29%22%22=%22%22cos%28x%29

sin%282x%29cos%28x%29%2Bcos%282x%29sin%28x%29%2Bsin%282x%29cos%28x%29-cos%282x%29sin%28x%29%22%22=%22%22cos%28x%29

%22%22=%22%22cos%28x%29

2sin%282x%29cos%28x%29%22%22=%22%22cos%28x%29

2sin%282x%29cos%28x%29-cos%28x%29%22%22=%22%220

cos%28x%29%282sin%282x%29%5E%22%22-1%29%22%22=%22%220

cos%28x%29%22%22=%22%220; 2sin%282x%29%5E%22%22-1%7D%7D%29%7B%7B%7B%22%22=%22%220

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cos%28x%29%22%22=%22%220
x%22%22=%22%22matrix%281%2C3%2Cpi%2F2%2C%22%2C%22%2C3pi%2F2%29 <-- two solutions

2sin%282x%29-1%22%22=%22%220

2sin%282x%29%22%22=%22%221

sin%282x%29%22%22=%22%221%2F2

2x%22%22=%22%22

x%22%22=%22%22  <-- four more solutions

Edwin