#LHS=sqrt((1+cos theta)/(1-cos theta))#
#=sqrt(((1+cos theta)(1+costheta))/((1-costheta)(1+cos theta)))#
#=sqrt((1+cos theta)^2/((1-cos^2theta))#
#=sqrt((1+cos theta)^2/sin^2theta)#
#=(1+cos theta)/sintheta#
#=1/sintheta+cos theta/sintheta#
#=csctheta+cottheta=RHS#
Proved