SOLUTION: If p = cos x + cos 2x and q = sin x + sin 2x, find the value of 2pq.

Question 1140243: If p = cos x + cos 2x and q = sin x + sin 2x, find the value of 2pq.
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
If p = cos x + cos 2x and q = sin x + sin 2x, find the value of 2pq.
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2pq = 2*(cos(x) + cos(2x))*(sin(x) + sin(2x))
= 2*(sin(x)cos(x) + sin(x)*sin(2x) + cos(2x)*sin(x) + cos(2x)*sin(2x))

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