Question

Prove that sin 20 sin 4o sin 60 sin 80 = 3/16​

Answer 1

Step-by-step explanation:

sin 20 sin 40 sin 60 sin 80

we know

sin theta.sin (60-theta).sin(60+theta) = sin3 theta/4

sin 20 sin 4o sin 60 sin 80

sin 20 sin 4o sin 80 .sin60

sin3(20)/4 . √3/2

√3/8 .√3/2

3/16

Hehehe completed

Answer 2

Answer:

sin20. sin 40. sin60. sin80 

=> sin60[sin20.sin40.sin80] 

=>√3/2[sin20.sin(60-20).sin(60+20)] 

=>√3/2[sin 3(20)/4] 

=>√3/2[sin 60/4] 

=>√3/2[√3/2*4] 

=>√3/2*√3/8 

=3/16 

 

hope it's help u