The direction cosines of vector a=3hati+...

The direction cosines of vector `a=3hati+4hatj+5hatk` in the direction of positive axis of X, is

A

A. `+-(3)/(sqrt(50))`

B

B. `(4)/(sqrt(50))`

C

C. `(3)/(sqrt(50))`

D

D. `-(4)/(sqrt(50))`

Verified by Experts

The correct Answer is:

C

`(3)/(sqrt(3^(2)+4^(2)+5^(2)))=(3)/(sqrt(50))`.

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