If a line makes angles (alpha)/(2), (be...

If a line makes angles `(alpha)/(2), (beta)/(2), (gamma)/(2)` with co-ordinate axes,
then `cos alpha+cos beta+cos gamma=`

A

(a) `1`

B

(b) `-1`

C

(c) `2`

D

(d) `3`

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The correct Answer is:

B

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