Question Number 10415 by okhema francis last updated on 08/Feb/17

find all the possible values of cos θ such that 2cot ^2 θ + cos θ=0

Answered by last updated on 08/Feb/17

2(((cos^2 θ)/(sin^2 θ)))+cosθ=0  2cos^2 θ+cosθsin^2 θ=0  cosθ(2cosθ+sin^2 θ)=0  cosθ=0  2cosθ+sin^2 θ=0  2cosθ+1−cos^2 θ=0  cos^2 θ−2cosθ−1=0  cosθ=((2±2(√2))/2)  hence cosθ=0,((1±(√2))/)

Commented byokhema francis last updated on 09/Feb/17

thank you very much and let the lord be with you