If `alpha=pi/3`, prove that `cosalphacos2alphacos3alphacos4alphacos5al – InterviewSolution

InterviewSolution

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