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The direction cosines of a vector a are ...

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

A

`4 hat(i) + hat(j) + 3hat(k)`

B

`4 hat(i) + 5 hat(j) + 3hat(k)`

C

`4hat(i) - 5hat(j) - 3 hat(k)`

D

`hat(i) + hat(j) - hat(k)`

Text Solution

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The correct Answer is:
B
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