If sin θ + sin² θ = 1, then cos² θ + cos^4θ =?
a. -1
b. 0
c. 1
d. 2
Answers
Answered by
3
Step-by-step explanation:
sinø+sin²ø=1
sinø=1-sin²ø
sinø=cos²ø
cos²ø+cos⁴ø=cos²ø+(cos²ø)²
=cos²ø+(sinø)²
=cos²ø+sin²ø=1
c.1
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