SOLUTION: Show that (a) sin 2theta * cos theta + cos 2theta * sin theta = sin 4theta * cos theta - cos 4theta * sin theta

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Question 1209635: Show that
(a) sin 2theta * cos theta + cos 2theta * sin theta = sin 4theta * cos theta - cos 4theta * sin theta
Answer by mccravyedwin(407) About Me  (Show Source):
You can put this solution on YOUR website!
sin%282theta%29%2Acos%28theta%29+%2B+cos%282theta%29%2Asin%28theta%29%22%22=%22%22sin%284theta%29%2Acos%28theta%29+-+cos%284theta%29%2Asin%28theta%29

Use the identities:

sin%28A+%2B-+B%29%22%22=%22%22sin%28A%29cos%28B%29+%2B-+cos%28A%29sin%28B%29

sin%282theta%2Btheta%29%22%22=%22%22sin%284theta-theta%29

sin%283theta%29%22%22=%22%22sin%283theta%29

Edwin