How do you express sin theta - cot theta + tan^2 theta sinθcotθ+tan2θ in terms of cos theta cosθ?

1 Answer
Jun 7, 2016

(1-cos theta-cos^2 theta)/sqrt(1-cos^2 theta)+1/cos^2 theta-11cosθcos2θ1cos2θ+1cos2θ1

Explanation:

Only Pythagotean identity is used here:
sin^2 theta+cos^2 theta=1sin2θ+cos2θ=1

sin theta-cot theta +tan^2 theta=sin theta-cos theta/sin theta+sin^2 theta/cos^2 theta=(sin^2 theta-cos theta)/sin theta+(1-cos^2 theta)/cos^2 theta=(1-cos theta-cos^2 theta)/sqrt(1-cos^2 theta)+1/cos^2 theta-1sinθcotθ+tan2θ=sinθcosθsinθ+sin2θcos2θ=sin2θcosθsinθ+1cos2θcos2θ=1cosθcos2θ1cos2θ+1cos2θ1

I think it's the simplest form.