Question

Integral sinx/cos^2x dx adlh

Answer 1

∫sinx/cos^2x dx = ∫sinx/cos^2x d(cosx)/(-sinx)
= ∫-1/cos^2x d(cosx)
= -∫1/cos^2x d(cosx)
= -∫cos^(-2)x d(cosx)
= -(1/(-1.cosx)) + C
= 1/cosx + C