Question 1011314
If <a + <b = 270°, which of the following is equal to cos a? Show all steps.
a = 270-b
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sin(a) = sin(270-b) = sin(270)*cos(b)-cos(270)sin(b) = -cos(b) - 0 = -cos(b)
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Cheers,
Stan H.
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H. - cos B

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Cheers,
Stan H.
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