Question

tan3a-1/tan a-1=sec2a+tan a

Answer 1

Here is the answer:-

tan^3A-1/tanA-1

=(tanA-1)(tan^2A+1+tanA)/(tanA-1)

=tan^2A+1+tanA

=sec^2A+tanA(proved)[sec^2A-tan^2A=1]

HoPe it will help you