Prove that sin20.sin40.sin60.sin80=3/16

Steps to prove sin20.sin40.sin60.sin80=3/16

L.H.S

=sin20.sin40.sin60.sin80

=√3/2.sin20.sin40.sin80

=√3/2.sin20.sin(60-20).sin(60+20)

=√3/2.1/4.sin3(20)

=√3/2.1/4.rt3/2

=3/16

=R.H.S

Hence sin20.sin40.sin60.sin80=3/16 is proved

Detail Information:-

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