Question

How to verify the identity tan(x+pi/2)=-cotx ?

Answer 1

DoI use the cofunction identiy first?

Answer 2

Well, one way would be to expand this in terms of the basic functions:

\[\tan x = \frac{\sin x}{\cos x}\]\[\cot x = \frac{\cos x}{\sin x}\]and work through it using the identities for the sin and cos of a sum