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Assertion (A) : "sin" (pi)/(n)+"sin" (3p...

Assertion (A) : `"sin" (pi)/(n)+"sin" (3pi)/(n)+"sin"(5pi)/(n)+....+` to n terms=0
Reason (R) : `sin alpha+ sin (alpha+ beta)+...+` to n terms `=(Sin ((n beta)/(2)))/(Sin beta//2)xxsin ((2 alpha+(n-1)beta)/(2))`

A

A is true R, is true ` R rArr A`

B

A is true R is true but `R cancel rArr A`

C

A is true, R is false

D

A is false, R is true

Text Solution

Verified by Experts

The correct Answer is:
A
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