If vec(A) xx vec(B) = 0 and vec(A).vec(B) = - AB the angle between vec(A) and vec(B) is

If vec(A) xx vec(B) = 0 and vec(A).vec(B) = - AB the angle between vec

1.	If vec(A) xx vec(B) = 0 and vec(A).vec(B) = - AB the angle between vec(A) and vec(B) is
Answer» 0 `(PI)/(4)` `(pi)/(2)` `pi` ANSWER :D