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In a triangle ABC, if a = 2, b = 3 and c...

In a triangle ABC, if `a = 2, b = 3 and c=4`, then `cos A` is equal to

A

`(7)/(8)`

B

`(1)/(3)`

C

`(1)/(2)`

D

`(1)/(sqrt(3))`

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A
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