Prove that cos^4A + sin^4A +2cos^2 = 1+2cos^4A
Answers
Answered by
0
cos
4
A−sin
4
A+1=(cos
2
A−sin
2
A)(cos
2
A+sin
2
A)+1
=cos
2
A−sin
2
A+1
=cos
2
A+cos
2
A
=2cos
2
A
4
A−sin
4
A+1=(cos
2
A−sin
2
A)(cos
2
A+sin
2
A)+1
=cos
2
A−sin
2
A+1
=cos
2
A+cos
2
A
=2cos
2
A
Similar questions