Let `hat a ,hat b,hat c`are three unit vectors such that `hata+hat b + hat c` is also a unit vector. If pairwise angles between `hat a,hat b, hat c` are `theta_1,theta_2,theta_3` rexpectively then `cos theta_1,+cos theta_2+ cos theta_3`, equals

If hat(a) and hat(b) are unit vectors such that (hat(a) + hat(b)) is a unit vector, what is the angle between hat(a) and hat(b) ?

If hat(a) and hat(b) are unit vectors such that (hat(a) + hat(b)) is a unit vector, what is the angle between hat(a) and hat(b) ?

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_2 and theta_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 and theta_3 . a. all are acute angles b. all are right angles c. at least one is obtuse angle d. none of these

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 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 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 hat a and hat b are unit vectors such that [ hata hatb hatatimeshatb ]= (1)/(4) ,then the angle between hat a and hat b ,is equal to

Let hat a , hat b , hatc be unit vectors such that hat a * hatb =hat a *hatc =0 and the angle between hat b and hat c be (pi)/(6) prove that hat a =+- 2 (hatb xx hat c )