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If alpha=pi/3, prove that cosalphac...

If `alpha=pi/3`, prove that
`cosalphacos2alphacos3alphacos4alphacos5alphacos6alpha=-1/16`

Text Solution

Verified by Experts

`cosalphaxxcos2alphaxxcos3alphaxxcos4alphaxxcos5alphaxxcos6alpha`
`=cos. pi/3xxcos. (2pi)/3xxcos. pixxcos. (4pi)/3xxcos. (5pi)/3xxcos. (6pi)/3`
`=1/2xx(-1/2)(-1)(-1/2)(1/2)1`
`=-1/16`
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