Question

If sin θ + sin² = 1, then cos²θ + cos4θ =
A. −1
B. 1
C. 0
D. None of these

Answer 1

Answer:

I think answer is 1

if it is correct make it brainlistt....

Answer 2

B. 1

Step-by-step explanation:

Given: sin θ + sin²θ = 1

Find: cos²θ + cos⁴θ

Solution:

sinθ + sin²θ = 1

sinθ = 1 - sin²θ

sinθ = cos²θ ---------(1)

(sinθ)² = (cos²θ)²

sin²θ = cos⁴θ

1 - cos²θ = cos⁴θ

cos⁴θ + cos²θ = 1

Option B is the answer.