#LHS=(cosA-sinA+1)/(cosA+sinA-1)#
#=(sinA(cosA-sinA+1))/(sinA(cosA+sinA-1))#
#=(sinAcosA-sin^2A+sinA)/(sinA(cosA+sinA-1))#
#=(sinAcosA+sinA-(1-cos^2A))/(sinA(cosA+sinA-1))#
#=(sinA(cosA+1)-(1-cosA)(1+cosA))/(sinA(cosA+sinA-1))#
#=((1+cosA)(sinA+cosA-1))/(sinA(cosA+sinA-1))#
#=((1+cosA)cancel((sinA+cosA-1)))/(sinAcancel((cosA+sinA-1)))#
#=1/sinA+cosA/sinA#
#=cscA+cotA=RHS#
Proved