Question

if sin A + sin ²A = 1 then cos²A + cos ⁴A=____​

Answer 1

Answer:

1 is the correct answer.

Answer 2

Answer:

1

Step-by-step explanation:

sin A + sin ²A = 1

sin A + sin ²A = sin ²A + cos²A          ( sin ²A + cos²A = 1 )

sin A = cos²A                                         -1

cos²A + cos ⁴A

= sin A +  cos ⁴A                                  ( from 1 )

= sin A + ( cos²A ) ( cos²A )                ( from 1 )

= sin A + ( sin A ) ( sin A )                   ( from 1 )

= sin A + sin ²A

= 1