If ` hat a , hat b ,a n d hat c` are three unit vectors inclined to each other at angle `theta,` then the minimum value of `theta` is `pi/3` b. `pi/4` c. `(2pi)/3` d. `(5pi)/6`

If widehat a and hat b are two unit vectors inclined at an angle theta, then sin((theta)/(2))

If widehat aandhat b are unit vectors inclined at an angle theta, then prove that (sin theta)/(2)=(1)/(2)|widehat a-hat b|

If \ vec a\ a n d\ vec b are two unit vectors inclined at an angle theta such that |a+b|,1, then theta (2pi)/3 c. pi/3

If theta is the angle between the unit vectors hat a and hat b then cos (theta/2) is equal to

If hat a , hat b ,a n d hat c are three unit vectors, such that hat a+ hat b+ hat c is also a unit vector and theta_1,theta_2a n dtheta_3 are angles between the vectors hat a , hat b ; hat b , hat ca n d hat c , hat a respectively, then among theta_1,theta_2,a n dtheta_3dot a. all are acute angles b. all are right angles c. at least one is obtuse angle d. none of these

If vec a and vec b be two unit vectors and theta is the angle between them.Then vec a+vec b is an unit vector,if theta=(pi)/(2) b.(2 pi)/(3) c.(pi)/(4) d.(pi)/(3)

If hata and hatb are two unit vectors and theta is the angle between them then vector 2hatb+hata is a unit vector if (A) theta= pi/3 (B) theta=pi/6 (C) theta=pi/2 (D) theta=pi

If unit vector a makes angles pi/3 with i, pi//4 with j and theta in (0,pi) with k, then a value of theta is