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If alpha, beta, gamma are lenghts of int...

If `alpha, beta, gamma` are lenghts of internal bisectors of angles A,B,C respectively of `DeltaABC`, then `sum (1)/(alpha) "cos" (A)/(2)` is

A

`a + b + c `

B

`1/a + 1/b + 1/c`

C

`2(1/a + 1/b + 1/c)`

D

`2(a + b + c)`

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The correct Answer is:
C
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AAKASH SERIES-PROPERTIES OF TRIANGLES-LECTURE SHEET EXERCISE - III (Straight Objective Type Question)
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