SOLUTION: which expression is equivalent to cos(5 theta) plus cos(3 theta)

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Question 885442: which expression is equivalent to cos(5 theta) plus cos(3 theta)
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
which expression is equivalent to cos(5 theta) plus cos(3 theta)
use x for theta
Sum-to-Product Formula:
cos5x%2Bcos3x=2cos%28%285x%2B3x%29%2F2%29cos%28%285x-3x%29%2F2%29=2cos4x%2Acosx