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If mtan(theta-30^@)=ntan(theta+120^@), t...

If `mtan(theta-30^@)=ntan(theta+120^@)`, then `cos2theta` is equal to

A

`(m-n)/(2(m+n))`

B

m+n

C

`(m+n)/(2(m-n))`

D

m-n

Text Solution

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The correct Answer is:
C
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