Question 174665
If sin(2theta + 18) = cos(5theta - 12), which of the follwoing pairs of angles are represented in this equation?
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Note; if sin(A) = cos(B), A and B are complementary: A+B = 90
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Your Promlem:
2theta + 18 + 5theta-12 = 90
7theta + 6 = 90
7theta = 84
theta = 12 degrees
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2theta+18 = 24+18 = 42 (one of the angles)
5theta-12 = 5*12 -12 = 48 (the other angle)

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Cheers,
Stan H.

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(a)42, 48 degrees
(b)38, 52 degrees
(c) 12, 68 degrees
(d) 45, 45 degrees