1.
The two vectors A\vec{A} and B\vec{B} are drawn from a common point and C=A+B\vec{C} = \vec{A} + \vec{B}, then angle between A\vec{A} and B\vec{B} is:
(1) 9090^\circ if C2=A2+B2C^2 = A^2 + B^2
(2) greater than 9090^\circ if C2<A2+B2C^2 < A^2 + B^2
(3) greater than 9090^\circ if C2>A2+B2C^2 > A^2 + B^2
(4) less than 9090^\circ if C2>A2+B2C^2 > A^2 + B^2
Correct options are: