If `A(veca),B(vecb),C(vecc) and D(vecd) ` are such that `3veca+8vecb=6vecc+5vecd` then the lines AB and CD are (A) parallel (B) intersecting (C) skew (D) none of these

If veca,vecb,vecc and vecd are unit vectors such that (vecaxxvecb)*(veccxxvecd)=1 and veca.vecc=1/2, then

veca.(vecbxxvecc) is called the scalar triple product of veca,vecb,vecc and is denoted by [veca vecb vecc] . If veca,vecb,vecc are coplanar then [veca+vecb vecb+vecc vecc+veca ] = (A) 1 (B) -1 (C) 0 (D) none of these

Let veca,vecb,vecc be three unit vectors such that 3veca+4vecb+5vecc=vec0 . Then which of the following statements is true? (A) veca is parrallel to vecb (B) veca is perpendicular to vecb (C) veca is neither parralel nor perpendicular to vecb (D) veca,vecb,vecc are copalanar

If veca,vecb,vecc and vecd are unit vectors such that (vecaxxvecb).(veccxxvecd)=1 and veca.vecc=1/2 then (A) veca,vecb,vecc are non coplanar (B) vecb,vecc, vecd are non coplanar (C) vecb, vecd are non paralel (D) veca, vecd are paralel and vecb, vecc are parallel

If (veca xx vecb) xx (vecc xx vecd) . (veca xx vecd) =0 then which of the following may be true ?

If [(2veca+4vecb,vecc,vecd)]=lamda[(veca,vecc,vecd)]+mu[(vecb,vecc,vecd)] , then lamda+mu=

If veca,vecb and vecc are unit vectors such that veca+vecb+vecc=vec0 then the value of veca.vecb+vecb.vecc+vecc.veca is a) 1 b) 0 c) 3 d) -3/2

The non zero vectors veca,vecb, and vecc are related byi veca=8vecb nd vecc=-7vecb. Then the angle between veca and vecc is (A) pi (B) 0 (C) pi/4 (D) 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

If veca,vecb,vecc are three unit vectors such that veca+vecb+vecc=0, then veca.vecb+vecb.vecc+vecc.veca is equal to (A) -1 (B) 3 (C) 0 (D) -3/2