Home
Class 12
MATHS
If a and b are two non collinear vectors...

If a and b are two non collinear vectors; then every vector r coplanar with a and b can be expressed in one and only one way as a linear combination: xa+yb=0.

A

(a)x=0, but y is not necessarily zero

B

(b)y=0, but x is not necessarily zero

C

(c)x=0,y=0

D

(d)none of these

Text Solution

Verified by Experts

The correct Answer is:
C

If a and b are two non-zero, non-collinear vectors and x and y are two scalars such that xa+yb=0 then x=0 and y=0 because one will be a scalar multiple off the other and hence collinear which is a contradiction.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • VECTOR ALGEBRA

    ARIHANT MATHS|Exercise VECTOR ALGEBRA EXERCISES 1: Single Option Correct Type Questions|1 Videos
  • VECTOR ALGEBRA

    ARIHANT MATHS|Exercise Exercise (More Than One Correct Option Type Questions)|7 Videos
  • VECTOR ALGEBRA

    ARIHANT MATHS|Exercise Exercise For Session 3|11 Videos
  • TRIGONOMETRIC FUNCTIONS AND IDENTITIES

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|18 Videos

Similar Questions

Explore conceptually related problems

If a and b are two non-zero and non-collinear vectors then a+b and a-b are

If vec a and vec b are two collinear vectors then which of the following are incorrect :

If a, b and c are non-collinear unit vectors also b, c are non-collinear and 2atimes(btimesc)=b+c , then

If vec a and vec b are non-collinear proper vectors then number of unit vectors at right angles to both vec a and vec b is........

What is meant by resolution of vector ? Prove that a vector can be resolved along two given directions in one and only way.

Given four non zero vectors bar a,bar b,bar c and bar d . The vectors bar a,bar b and bar c are coplanar but not collinear pair by pairand vector bar d is not coplanar with vectors bar a,bar b and bar c and hat (bar a bar b) = hat (bar b bar c) = pi/3,(bar d bar b)=beta ,If (bar d bar c)=cos^-1(mcos beta+ncos alpha) then m-n is :

a and b are non-collinear vectors. If c=(x-2) a+b and d=(2x+1)a-b are collinear vectors, then find the value of x.

If a,b and c are non-coplanar vectors, prove that 3a-7b-4c, 3a-2b+c and a+b+2c are coplanar.

If a and b are non-zero and non-collinear vectors, then show that axxb=["a b i"]hati+["a b j"]hatj+["a b k"]hatk

Consider three vectors vecp=hati+hatj+hatk,vecq=2hati+4hatj-hatk and vecr=hati+hatj+3hatk and let vecs be a unit vector, then vecp,vecq and vecr are a. linealy dependent b. can form the sides of a possible triangle c. such that the vectors (q-r) is orthogonal to p d. such that each one of these can be expressed as a linear combination of the other two