Question

sinx + sin²x=1. Prove that
cos^12x+3cos^10x+3cos^8x+cos^6=1​

Answer 1

Step-by-step explanation:

you can proceed this ,

sinx + sin^2x =1

sinx =1 - sin^2x =cos^2x

now,

cos^12x+3cos^10x +3cos^8x +cos^6x

=> (cos^4x)^3+3. (cos^4x)^2.cos^2x +3cos^4x.(cos^2x)^2+(cos^2x)^3

=>(sin^2x)^3+3sin^4x.cos^2x+3sin^2x.cos^4x +(cos^2x)^3

=>{sin^2x+ cos^2x}^3 = 1^3 =1