If `vec P xx vec Q= vec R, vec Q xx vec R= vec P` and `vec R xx vec P = vec Q` then

If vec p xxvec q=vec r and vec p*vec q=c, then vec q is

If vec p + vec q + vec r = xvec s and vec q + vec r + vec s = yvec p and are vec p, vec q, vec r non coplaner vectors then | vec p + vec q + vec r + vec r + vec s | =

If vec r=3vec p+4vec q and 2vec r=vec p-3vec q then

If vec p = vec a + vec b, vec q = vec a-vec b | vec a | = | vec b | = 1 then | vec p xxvec q | =

if vec(P) xx vec(R ) = vec(Q) xx vec(R ) , then

If vec a,vec b,vec c be any three non-zero non coplanar vectors and vectors vec p=(vec b xx vec c)/(vec a.vec b xx vec c),vec q=(vec c xx vec a)/(vec a.vec b xx vec c) vec r=(vec a xx vec b)/(veca.vec b xx vec c), then [vec p vec q vec r] equals -

If |vec P xx vec Q|=PQ then the angle between vec P and vec Q is

Let vec(a)= vec(i) + vec(j), vec(b)= 2vec(j)-vec(k) . If vec(r ) xx vec(a) = vec(b) xx vec(a), vec(r ) xx vec(b) = vec(a) xx vec(b) , then (vec(r ))/(|vec(r )|) =

Prove that [vec a xxvec p, vec b xxvec q, bar (c) xxbar (r)] + [vec a xxvec q, vec b xxvec r, vec c xxvec p] + [vec a xxvec r, vec b xxvec p , vec c xxvec q]