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In A B C , the median A D divides /B A ...

In ` A B C ,` the median `A D` divides `/_B A C` such that `/_B A D :/_C A D=2:1` . Then `cos(A/3)` is equal to `(sinB)/(2sinC)` (b) `(sinC)/(2sinB)` `(2sinB)/(sinC)` (d) `non eoft h e s e`

A

`(sinB)/(2 sin C)`

B

`(sin C)/(2 sin B)`

C

`(2 sin B)/(sin C)`

D

None of these

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A
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