SOLUTION: I need to prove that (2sinx+3cosx)^2 + (3sinx-2cosx)^2 = 13 work would be appreciated. thank you

Question 427300: I need to prove that
(2sinx+3cosx)^2 + (3sinx-2cosx)^2 = 13
work would be appreciated. thank you
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
Expand the left side:

The terms cancel out, leaving

Collect like terms to obtain

. Since we conclude that the entire expression is equal to 13.
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