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If vec(A)=2 hat(i) + 3 hat(j) - hat(k) a...

If `vec(A)=2 hat(i) + 3 hat(j) - hat(k)` and `vec(B)= 4 hat(i) + 6 hat(j) -2 hat(k)` the angle between `vec(A)` and `vec(B)`will be:

A

`pi`

B

`pi/3`

C

`pi/2`

D

`0^@`

Text Solution

Verified by Experts

The correct Answer is:
D
`costheta=(vec(A).vec(B))/(AB)`
`costheta=((2hati + 3hatj - hatk).(4hati + 6hatj - 2hatk))
(sqrt(4+9+1)sqrt(16+36+4))`
`costheta=28/28=1`
`implies theta=0^@`
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