If A is not an integral multiple of (pi)...

If A is not an integral multiple of `(pi)`, prove that `cos A cos 2A cos 4A cos 8A =(sin 16A)/(16 sin A)` Hence deduce that `cos. (2pi)/(15). Cos. (4pi)/(15) .cos. (8pi)/(18). Cos. (16pi)/(15)=(1)/(16)`

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Step by step text solution for If A is not an integral multiple of (pi), prove that cos A cos 2A cos 4A cos 8A =(sin 16A)/(16 sin A) Hence deduce that cos. (2pi)/(15). Cos. (4pi)/(15) .cos. (8pi)/(18). Cos. (16pi)/(15)=(1)/(16) by MATHS experts to help you in doubts & scoring excellent marks in Class 11 exams.

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cos. (pi)/(13) + cos. (5pi)/(13) + cos. (8pi)/(13) + cos. (12pi)/(13)=

-1

cos""(2pi)/(15) cos ""(4pi)/(15)""cos(8pi)/(15) cos""(16pi)/(15)=

`1//4`

`1//8`

`1//16`

`1//32`

cos. (3pi)/(19) + cos . (7pi)/(19) + cos. (12pi)/(19) + cos. (16pi)/(19) =

-1