Question 293364
how to find the exact value of cos(arcsin(-1/2) + arctan(2/3))
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Form: cos(a+b) = cos(a)*cos(b)-sin(a)*sin(b)
Your "a" is arcsin(-1/2) = -30 degrees
Your "b" is arctan(2/3) = 33.69 degrees
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Your Problem:
= cos(-30)cos(33.69)-sin(-30)sin(33.69)
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= (sqrt(3)/2)(3/sqrt(13)) - (-1/2)(2/sqrt(13))
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Cheers,
Stan H.
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