Prove that 8sin10.sin50.sin70=1

 Steps to prove 8sin10.sin50.sin70=1 

Take L.H.S 8sin10.sin50.sin70

= 8sin10.sin50.sin70 

= 8sin10.sin(60-10).sin(60+10)

[ sinA.sin(60-A).sin(60+A)=1/4sin3A ]

= 8/4 sin 3x10

= 2 sin30 = 2 x 1/2

= 1 

= R.H.S

∴  Hence 8sin10.sin50.sin70=1 is proved

Detail information:-

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