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:

If vec(A)=2 hat(i) + 3 hat(j) - hat(k) and vec(B)= 4 hat(i) + 6 hat(j)

1.	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:
Answer» `pi` `pi/3` `pi/2` `0^@` Solution :`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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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:

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