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In triangle A B C , if sinAcosB=1/4a n d...

In triangle `A B C ,` if `sinAcosB=1/4a n d3t a n A=t a n B ,t h e ncot^2A` is equal to 2 (b) 3 (c) 4 (d) 5.

A

2

B

3

C

4

D

5

Text Solution

Verified by Experts

The correct Answer is:
B
`3 sin A cos B=sin B cos A`
`rArr cos A sin B =(3)/(4)`
`rArr C=(pi)/(2).B=(pi)/(2)-A`
`rARr 3tan A=tan ((pi)/(2)-A)`
`rArr 3=cot^(2)A`.
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