Question

If cos A +cos²A = 1, then sin² A + sin⁴ A is​

Answer 1

CosA+cos² A = 1

=> cosA = 1-cos² A

=> cos A = sin² A

(since 1-cos² A = sin² A)

Squaring both sides we get

cos²A = sin⁴ A

=> (1-sin²A) = sin⁴ A

( since cos² A=1-sin^2 A)

=> 1 = sin⁴A + sin² A

or Sin⁴A + SIN ²A =1

Answer 2

Answer:

Step-by-step explanation:

CosA+cos² A = 1

=> cosA = 1-cos² A

=> cos A = sin² A

(since 1-cos² A = sin² A)

Squaring both sides we get

cos²A = sin⁴ A

=> (1-sin²A) = sin⁴ A

( since cos² A=1-sin^2 A)

=> 1 = sin⁴A + sin² A

or Sin⁴A + SIN ²A =1