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The direction cosines of a vector vecA a...

The direction cosines of a vector `vecA` are `cos alpha=(4)/(5sqrt(2)),cos beta =(1)/(sqrt(2)) and cos gamma=(3)/(5sqrt(2))` then the vector `vecA` is

A

`4hati+hatj+3hatk`

B

`4hati+5hatj+3hatk`

C

`4hati-5hatj-3hatk`

D

`hati+hatj-hatk`

Text Solution

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The correct Answer is:
B
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