Let vectors `veca, vecb veca and vecd` be such that `(veca xxvecb)xx (veccxxvecd)=vec0. " Let " P_(1)and P_(2)` be planes determined by the pairs of vectors `veca,vecb and vecc ,vecd` , respectively. Then the angle between `P_(1) and P_(2)` is

Let the vectors veca, vecb,vecc and vecd be such that (vecaxxvecb)xx(veccxxvecd)=vec0 . Let P_1 and P_2 be planes determined by pairs of vectors veca,vecb and vecc,vecd respectively. Then the angle between P_1 and P_2 is (A) 0 (B) pi/4 (C) pi/3 (D) pi/2

If the vectors veca, vecb, vecc, vecd are coplanar show that (vecaxxvecb)xx(veccxxvecd)=vec0

Let the pair of vector veca,vecb and vecc,vecd each determine a plane. Then the planes are parallel if

If the vectors veca, vecb, vecc and vecd are coplanar vectors, then (vecaxxvecb)xx(veccxxvecd) is equal to

if veca , vecb ,vecc are three vectors such that veca +vecb + vecc = vec0 then

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

for any four vectors veca,vecb, vecc and vecd prove that vecd. (vecaxx(vecbxx(veccxxvecd)))=(vecb.vecd)[veca vecc vecd]

If three unit vectors veca, vecb and vecc " satisfy" veca+vecb+vecc= vec0 . Then find the angle between veca and vecb .

If veca + 2 vecb + 3 vecc = vec0 " then " veca xx vecb + vecb xx vecc + vecc xx veca=

Given vecC = vecA xx vecB and vecD = vecB xx vecA . What is the angle between vecC and vecD ?