Question

formula for. cos^4x+sin^4x
and.

cos
$cos^43x + sin ^43x$
​

Answer 1

Step-by-step explanation:

cos⁴x +sin⁴x

= (cos²x)² + ( sin²x)²

= (sin²x+ cos²x)² -2sin²xcos²x

= 1- 2sin²xcos²x

same for another

answer: 1- 2sin²3xcos²3x