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A line makes acute angles of alpha, beta...

A line makes acute angles of `alpha, beta and gamma` with the co-ordinae 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 ` is equal to : a)`(25)/(9)` b)`(5)/(9)` c)`(5)/(3)` d)`(2)/(3)`

A

`(25)/(9)`

B

`(5)/(9)`

C

`(5)/(3)`

D

`(2)/(3)`

Text Solution

Verified by Experts

The correct Answer is:
C
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