Question

How do you verify the identity `lnabs(cotx)+lnabs(tanxcosx)=lnabs(cosx)`?

Answer 1

Starting from the first part of the equation we have

#lnabs(cotx)+lnabs(tanxcosx)=lnabs(cotx*tanx*cosx)= lnabs(cosx/sinx*sinx/cosx*cosx)=lnabs(cosx)#