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Prove that: sin20^0sin40^0sin60^0sin80^0...

Prove that: `sin20^0sin40^0sin60^0sin80^0=3/(16)`

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Consider `LHS`

`sin 20 × sin 40 × sin60 × sin80`

`= sin60 [sin20 × sin40 × sin80]`

`= √3/2[sin20 × sin(60 – 20) × sin(60 + 20)]`

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sin20^(0)sin40^(0)sin60^(0)sin80^(@)=(3)/(16)

Prove that: sin20^(0)sin40^(0)sin60^(@)sin80^(@)=(3)/(16)

Prove that: sin20^(@)sin40^(0)sin60^(@)sin80^(@)=(3)/(16)

Prove that: i) sin20^(@)sin40^(@)sin60^(@)sin80^(@)=3/16 ii) sin10^(@)sin50^(@)sin60^(@)sin70^(@)=sqrt(3)/16 iii) sin20^(@)sin40^(@)sin80^(@)=sqrt(3)/8

Prove that: sin10^(0)sin30^(0)sin50^(@)sin70^(@)=(1)/(16)

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sin20^(@)sin40^(@)sin60^(@)sin80^(@)

prove that sin10^(0)+sin20^(0)+sin40^(@)+sin50^(0)=sin70^(0)+sin80^(@)

Prove that: sin20^(@)sin40^(@)sin80^(@)=(sqrt(3))/(8)

RD SHARMA-TRANSFORMATION FORMULAE-Solved Examples And Exercises
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