#sqrt((1+cos theta)/(1-cos theta)) #
multiply with #sqrt (1+cos theta)#
#sqrt((1+cos theta)/(1-cos theta))*sqrt((1+cos theta)/(1+cos theta)) #
#sqrt(((1+cos theta)/(1-cos theta))*((1+cos theta)/(1+cos theta)) #
#= sqrt((1+cos theta)^2/((1-cos^2 theta)) #
#= sqrt((1+cos theta)^2/sin^2 theta) = (1+cos theta)/sin theta#
#= 1/sin theta +cos theta/sin theta#
#=cosec theta + cot theta#