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If vec(A)= 2hat(i)+4hat(j)-5hat(k) then ...

If `vec(A)= 2hat(i)+4hat(j)-5hat(k)` then the direction of cosins of the vector `vec(A)` are

A

`(2)/(sqrt(45)),(4)/(sqrt(45))` and `(-5)/(sqrt(45))`

B

`(1)/(sqrt(45)),(2)/(sqrt(45))` and `(3)/(sqrt(45))`

C

`(4)/(sqrt(45)),0` and `(4)/(sqrt(45))`

D

`(3)/(sqrt(45)),(2)/(sqrt(45))` and `(5)/(sqrt(45))`

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The correct Answer is:
A
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