Question

if sin theta +sin^2 theta =1, then evaluate cos^2 theta + cos^4 theta

Answer 1

hope it will help you

Answer 2

Step-by-step explanation:

$sin\alpha +sin^{2}\alpha = 1$

$sin\alpha = 1-sin^{2} \alpha$

$sin\alpha=cos^{2} \alpha$

Now,

$cos^{2} \alpha + cos^{4} \alpha = sin \alpha + sin^{2} \alpha = 1$

∴ cos²α + cos⁴α = 1.