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Prove that :"sin"Asin(60^0-A)sin(60^0+A)...

Prove that :`"sin"Asin(60^0-A)sin(60^0+A)=1/4sin3A`

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we know that
`=>sin(A+B)sin(A−B)=sin^2A−sin^2B`
Now given,
`=>sinAsin(60−A)sin(60+A)=sinA(sin^2(60)−sin^2A)`
`=>.sinA(3/4−sin^2A)`
`=>(3sinA−4sin^3A​)/4`
`=>(​sin3A)/4`
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