Grade 12TrigonometryProve that sin20°. sin40°. sin60°. sin80° = 3/16 Shalini Rai 13 Years agoGrade 12
md salik13 Years ago=sin20 sin40 sin80 sin60 =1/4 sin60 sin 60 {sinx sin(60-x) sin(60+x)=1/4 sin 3x} =1/4 *(sin 60)2 =1/4 *3/4 =3/16 proved