Use a double- angle formula to rewrite?

Question

Please help me my teahcer didn't go over this and my final is on Thursday!! Please everyone come to my rescue!!!
Use a double- angle formula to rewrite:

2 sin 12 cos 12

cos^2 6a-sin^26a

thanks again

Answer 1

The sin(2a) = 2sin(a)cos(a) so, 2sin(12)cos(12) = sin(24).

cos(2a) = cos^2(a) - sin^2(a) so,
cos(12a) = cos^2(6a) - sin^2(6a).

Answer 2

2 sin θ cos θ = sin 2θ
2 sin 12° cos 12° = sin 24°

cos² 6a - sin² 6a = cos 12a

Answer 3

2sin(x)cos(x) = sin(2x)
Put x = 12.

cos^2(x) - sin^2(x) = cos(2x)
Put x = 6a.