buktikan bahwa Sin²A Cos²A = 1/8-1/8Cos 4A

sin² a cos² a
= (sin a cos a)²
= (1/2 . sin 2a)²
= (1/4) sin² 2a

➡ sin² 2a = (1 - cos 4a)/2

= (1/4)(1/2)(1 - cos 4a)
= (1/8)(1 - cos 4a)
= (1/8) - (1/8) cos 4a
= ruas kanan
TerBukTi