Question 138704
find the exact value of each function.
1. Cos 7pi/4 = cos (-1/4 pi) = cos (1/4 pi) = (sqrt(2))/2
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2. Sin (-30') = -sin30 = -1/2
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Find the reference angle for the angle with the given measure
1. 13pi/8: ref. angle= (3/8)pi
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2. -7pi/4; ref. angle = (1/4)pi
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Cheers,
Stan H.