Berapa hasil dari Sin 40° . Sin 20°

TriGonoMetRi

sin 40° sin 20°
= 1/2 (cos (40 - 20) - cos (40 + 20)
= 1/2 (cos 20° - 1/2)
= 1/4 (2 cos 20° - 1)

Sin 40 drajat =0,642
Sin 20 drajat =0,342

sin 40 drajat.sin 20 drajat
=0,642.0,342
=0,219564