How do you verify (tanx/(1+cosx)) + (sinx/(1-cosx))=cotx + secxcscx?

1 Answer
Apr 20, 2018

LHS=(tanx/(1+cosx)) + (sinx/(1-cosx))

=(tanx(1-cosx) + sinx(1+cosx))/(1-cos^2x)

=(tanx-tanxcosx + sinx+sinxcosx)/sin^2x

=(sinx/cosx-sinx/cosx*cosx + sinx+sinxcosx)/sin^2x

=(sinxsecx-cancelsinx +cancel sinx+sinxcosx)/sin^2x

=(sinxsecx)/sin^2x +(sinxcosx)/sin^2x

=secx/sinx +cosx/sinx

=cotx + secxcscx=RHS