Cos⁴A - cos²A = sin⁴A - sin²A

Answer- cos(2A) - 1

*** I'm not very sure of the answer. Because I'm not very good at math.

How to make-

cos⁴A - cos²A = sin⁴A - sin²A

= cos(A)⁴ -1 - sin(A)⁴

= (cos(A)² - sin(A)²) × (cos (A)² + sin(A)²) -1

= cos (2A) × (cos(A)² + sin(A)²) -1

= cos(2A) × 1 - 1

= cos(2A) - 1

the answer would be c:   ax + b = ax + c

step-by-step explanation: