How do you verify sec^2((pi/2)-x)-1=cot^2 xsec2((π2)x)1=cot2x?

1 Answer
Apr 22, 2016

Proof below

Explanation:

Identity: sec^2theta=1+tan^2thetasec2θ=1+tan2θ
sec^2(pi/2-x)-1=1+tan^2(pi/2-x)-1sec2(π2x)1=1+tan2(π2x)1
=tan^2(pi/2-x)=tan2(π2x)
Identity: tan(pi/2-theta)=cotthetatan(π2θ)=cotθ
=cot^2x=cot2x