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If the sides a, b, c of a triangle ABC are the roots of the equation `x^(3)-13x^(2)+54x-72=0`, then the value of `(cosA)/(a)+(cosB)/(b)+(cosC)/(c )` is equal to :

A

`169/144`

B

`61/72`

C

`61/144`

D

`169/72`

Text Solution

Verified by Experts

The correct Answer is:
C
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