pleasez dummies ! the simplest and preices solution is
first take Y=tan(x/2)
then differentiate it to get dx=(2/1+y^2)dy
and then take cos x = (1-y^2)/(1+y^2)
then put above values in equation of dx/(1+cosx) .then solve it by yourself its enough ! ohh one thingi have forgotten ...
pleasez dummies ! the simplest and preices solution is
first take Y=tan(x/2)
then differentiate it to get dx=(2/1+y^2)dy
and then take cos x = (1-y^2)/(1+y^2)
then put above values in equation of dx/(1+cosx) .then solve it by yourself its enough ! ohh one thingi have forgotten...