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If sin A sin (60^(@)-A)sin(60^(@)+A)=ksi...

If sin A sin `(60^(@)-A)sin(60^(@)+A)=ksin3A`, then what is k equal to ?

A

`1//4`

B

`1//2`

C

1

D

4

Text Solution

Verified by Experts

The correct Answer is:
A
`sinA*sin(60^(@)-A)sin(60^(@)+A)=ksin3A`
`[becausesin(60^(@)+A).sin(60^(@)-A)=(sin3A)/(4sinA)]`
`rArr(sin3A)/(4)=k.sin3A`
`thereforek=(1)/(4)`
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