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A line makes acute alpha, beta and gamma...

A line makes acute `alpha, beta` and `gamma` with the coordinate axes such that `cos alpha . Cos beta = cos beta . Cos gamma = 2/9` and `cos gamma . cos alpha = 4/9`, then `cos alpha + cos beta + cos gamma =`

A

`5/3`

B

`2/3`

C

`1/3`

D

`3/7`

Text Solution

Verified by Experts

The correct Answer is:
C
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