How would you solve a reduction identity. For example cot(x-90)? What are the steps to solving them besides graphing?

Answer 1

you could say
cot(x-90°) = tan(-x) = -tanx

there are 3 pairs of co-ratios

sine vs co-sine
tangent vs co-tangent
secant vs co-secant

for each of these
trigratio(x) = co-trigratio(90°-x)

Don't know if this answers your question.