Let `veca,vecb and vecc` be three unit vectors such that `vecaxx(vecbxxvecc)=sqrt(3)/2(vecb+vecc)`. If `vecb` is not parallel to` vecc` then the angle between `veca and vecb` is (A) `(5pi)/6` (B) `(3pi)/4` (C) `pi/2` (D) `(2pi)/3`

let veca, vecb and vecc be three unit vectors such that veca xx (vecb xx vecc) =sqrt(3)/2 (vecb + vecc) . If vecb is not parallel to vecc , then the angle between veca and vecb is:

If |veca.vecb|=sqrt(3)|vecaxxvecb| then the angle between veca and vecb is (A) pi/6 (B) pi/4 (C) pi/3 (D) pi/2

If veca, vecb and vecc are three unit vectors such that veca xx (vecb xx vecc) = 1/2 vecb , " then " ( vecb and vecc being non parallel)

If veca, vecb and vecc are three unit vectors such that veca xx (vecb xx vecc) = 1/2 vecb , " then " ( vecb and vecc being non parallel)

If veca,vecb and vecc are non coplanar and unit vectors such that vecaxx(vecbxxvecc)=(vecb+vecc)/sqrt(2) then the angle between vea and vecb is (A) (3pi)/4 (B) pi/4 (C) pi/2 (D) pi

If veca+vecb+vecc=0, |veca|=3, |vecb|=5, |vecc|=7, then angle between veca and vecb is (A) pi/6 (B) (2pi)/3 (C) (5pi)/3 (D) pi/3

If |vecc|=2 , |veca|=|vecb|=1 and vecaxx(vecaxxvecc)+vecb=vec0 then the acute angle between veca and vecc is (A) pi/6 (B) pi/4 (C) pi/3 (D) (2pi)/3

If veca, vecb, vecc are non-coplanar unit vectors such that vecaxx(vecbxxvecc)=(vecb+vecc)/(sqrt(2)) then the angle between veca and vecb is

If veca,vecb,vecc be three that unit vectors such that vecaxx(vecbxxvecc)=1/2 vecb, vecb and vecc veing non parallel. If theta_1 is the angle between veca and vecb and theta_2 is the angle between veca and vecb then (A) theta_1 = pi/6, theta_2=pi/3 (B) theta_1 = pi/3, theta_2=pi/6 (C) theta_1 = pi/2, theta_2=pi/3 (D) theta_1 = pi/3, theta_2=pi/2

If veca,vecb,vecc are unit vectors such that veca is perpendicular to vecb and vecc and |veca+vecb+vecc|=1 then the angle between vecb and vecc is (A) pi/2 (B) pi (C) 0 (D) (2pi)/3