If $cos^2 θ+cos^4θ=1,$ then the value of $sinθ +sin^2θ$ is :

0 $\frac{1}{2}$ 2 1

1

cos²θ + cos4θ = 1 cos4θ = 1 - cos²θ { using   sin²θ + cos²θ = 1 } cos4θ = sin²θ and cos²θ = sinθ Now, sinθ + sin²θ  = cos²θ + cos4θ = 1               { given :- cos²θ + cos4θ = 1 }