SOLUTION: Use the squared identities to simplify 2sin^2xsin^2x. I REALLY NEED HELP WITH THIS PROBLEM :((((

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Question 930463: Use the squared identities to simplify 2sin^2xsin^2x.


I REALLY NEED HELP WITH THIS PROBLEM :((((
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
3-4cos%282x%29%2Bcos%284x%29%2F4 is = 2sin%5E4%28x%29....
here is proof:
2sin%5E2%28x%29sin%5E2%28x+%29...use sin%5E2%28x%29=1-cos%5E2%28x%29

2%281-cos%5E2%28x%29%29%281-cos%5E2%28x%29%29+
2%281-cos%5E2%28x%29%29%5E2+
2%281-2cos%5E2%28x%29%2Bcos%5E4%28x%29%29

%282-4cos%5E2%28x%29%2B2cos%5E4%28x%29%29.........since

2-4cos%5E2%28x%29%2Bcos%282x%29%2Bcos%284x%29%2F4%2B3%2F4........and 4cos%5E2%28x%29=2+%28cos%282x%29%2B1%29

2-2%28cos%282x%29%2B1%29%2Bcos%282x%29%2Bcos%284x%29%2F4%2B3%2F4

cross%282%29-2cos%282x%29-cross%282%29%2Bcos%282x%29%2Bcos%284x%29%2F4%2B3%2F4

-cos%282x%29%2Bcos%284x%29%2F4%2B3%2F4

%281%2F4%29%28-4cos%282x%29%2Bcos%284x%29%2B3%29

%283-4cos%282x%29%2Bcos%284x%29%29%2F4
and
%283-4cos%282x%29%2Bcos%284x%29%29%2F4=2sin%5E4%28x%29 but it's NOT simplified form...:-)