If cosθ + cos2θ = 1, then
find the value of \(\sqrt {sin^4θ+cos^2θ}\)
Answer & explanation
Correct answer: option 2
⇒ cosθ = 1- cos2θ = sin2θ
⇒ cosθ = sin2θ and cos2θ = sin4θ
Now,
⇒ \(\sqrt {sin^4θ+cos^2θ}\) = \(\sqrt {cos^2θ+cos^2θ}\) = \(\sqrt {2}\)cosθ