Question

Given the identity tanX =sinX/cosX and the relationship between the sine and cosine of complementary angles, what is tan (90 -A)?

Answer 1

Base from the given that tan X =sin X / cos X. so the answer to the question what is tan ( 90 - A) is:
first let X = 90 - A
substituting from the given that 
tan X =sin X / cos X
tan ( 90 - A) = sin ( 90 - A)  / cos ( 90 - A) 

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