Question

How do i get left side to equal right side?

(1-tanx)/(1-cotx) = -tanx

Answer 1

(1-tanx)/(1-cotx)

(1-tanx)/(1 - 1/tanx)
(1-tanx)/((tanx-1)/tanx)
(1-tanx)(tanx) / (tanx-1)
-tanx