Question

If sin 0+sin²0 =1, then the value of cos²O + cos⁴O is
(A)3
(B) 2
(C) 1
(D)0​

Answer 1

Answer:

If sin 0+sin²0 =1, then the value of cos²O + cos⁴O is=(c)2

Answer 2

Answer:

sin θ+sin²θ =1

so

sin θ = 1 - sin²θ

by the identity 1-sin²θ = cos²θ

so we can say that

sinθ = cos²θ____________(1)

similarly the value of cos⁴θ

cos⁴θ = (cos²θ)²

cos⁴θ = sin²θ___________(2)

cos²θ + cos⁴θ        

= sinθ + sin²θ

= 1