RHS=sec2theta+tan2thetaRHS=sec2θ+tan2θ
=(1+tan^2theta)/(1-tan^2theta)+(2tantheta)/(1-tan^2theta)=1+tan2θ1−tan2θ+2tanθ1−tan2θ
=(1+tantheta)^2/((1-tantheta)(1+tantheta))=(1+tanθ)2(1−tanθ)(1+tanθ)
=(1+tantheta)/(1-tantheta)=1+tanθ1−tanθ
=(tan(pi/4)+tantheta)/(1-tan(pi/4)tantheta)=tan(π4)+tanθ1−tan(π4)tanθ
=tan(pi/4+theta)=LHS=tan(π4+θ)=LHS
Proved