`A B C D` is a quadrilateral. Find the sum the vectors ` vec B A` , ` vec B C ,` and ` vec D A` .

The position vectors of the vertices A ,Ba n dC of a triangle are three unit vectors vec a , vec b ,a n d vec c , respectively. A vector vec d is such that vecd dot vec a= vecd dot vec b= vec d dot vec ca n d vec d=lambda( vec b+ vec c)dot Then triangle A B C is a. acute angled b. obtuse angled c. right angled d. none of these

Give vec A + vec B+ vec C + vec D =0 , which of the following statements are correct ? (a) vec A, vec B ,vec C abd vec C must each be a null vector. (b) The magnitude of ( vec A + vec C) equals the magnitude of ( vec B + vec D0 . ltBrgt (c ) The magnitude of vec A can never be greater than the sum of the magnitude of vec B , vec C and vec D . ( d) vec B + vec C must lie in the plance of vec A + vec D. if vec A and vec D are not colliner and in the line of vec A and vec D , if they are collinear.

The vectors vec a,vec b,vec c,vec d are coplanar then

If vec(a), vec(b), vec(c ), vec(d) respectively, are position vectors representing the vertices A, B, C, D of a parallelogram, then write vec(d) in terms of vec(a), vec(b) and vec(c ) .

The position vectors of the vertices of a quadrilateral with A as origin are B(vec b),D(vec d) and C(lvec b+mvec d) Prove that the area of the quadrialateral is (1)/(2)(l+m)|vec b xxvec d|

A,B,C and D are four points in a plane with position vectors vec a,vec b,vec c and vec d, respectively,such that (vec a-vec d)*(vec b-vec c)=(vec b-vec d)*(vec c-vec a)=0 Then point D is the of triangle ABC

If vec a,vec b,vec c and vec d are the position vectors of the vertices of a cyclic quadrilateral ABCD prove that (|vec a xxvec b+vec b xxvec d+vec d xxvec a|)/((vec b-vec a)*(vec d-vec a))+(|vec b xxvec c+vec c xxvec d+vec d xxvec b|)/((vec b-vec c)*(vec d-vec c))=

Statement 1: vec a , vec b ,a n d vec c are three mutually perpendicular unit vectors and vec d is a vector such that vec a , vec b , vec ca n d vec d are non-coplanar. If [ vec d vec b vec c]=[ vec d vec a vec b]=[ vec d vec c vec a]=1,t h e n vec d= vec a+ vec b+ vec c Statement 2: [ vec d vec b vec c]=[ vec d vec a vec b]=[ vec d vec c vec a] =>vec d is equally inclined to veca,vecb,vecc.

If vec a , vec b , vec c and vec d are the position vectors of points A, B, C, D such that no three of them are collinear and vec a + vec c = vec b + vec d , then ABCD is a

36. If vec a, vec b, vec c and vec d are unit vectors such that (vec a xx vec b) .vec c xx vec d = 1 and vec a.vec c = 1/2 then a) vec a, vec b and vec c are non-coplanar b) vec b, vec c, vec d are non -coplanar c) vec b, vecd are non parallel d) vec a, vec d are parallel and vec b, vec c are parallel