Problem OneSin(90 + q) = sin(90)*cos(q) + sin(q)*cos(90)
sin(90 + q) = 1 * cos(q) + sin(q)*0
sin(90 + q) = cos(q)
You can elimate anything beginning with Cos
You can also eliminate the sin function with a minus between it.
Problem 2Sin(x) = 1/csc(x) That makes C and D incorrect.
Correct answer has to be A. Since this is a multiple choice question you can't qualify the answer, but there are some points that exhibit questionable behavior, like 2
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*f*t = 0 for example. The function becomes undefined.