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If, in a /\ ABC, (2 cos A)/a + (cos B)...

If, in a `/_\ ABC`,
`(2 cos A)/a + (cos B)/(b) + (2 cos C)/(c) = a/(bc) + b/(ca)`,
then: `/_A = .....`

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The correct Answer is:
`/_A = 90^(@)`
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