Home
Class 12
MATHS
Let veca, vecb and vecc be three non-zer...

Let `veca, vecb and vecc` be three non-zero vectors such that no two of these are collinear.If the vector `veca + 2 vecb` is collinear with `vecc and vecb +3 vecc` is collinear with `veca (lamda` being some non-zero scalar), then` veca + 2 vecb + 6 vecc` equals:

A

`lamda a`

B

`lamdab`

C

`lamda c`

D

`0`

Text Solution

Verified by Experts

The correct Answer is:
D

If a+2b is collinear with c, then a+2b=tc . . . (i)
also, b+3c is collinear with a, then
`b+3c=lamda a`
`implies b=lamda a-3c` . . (ii)
from eqs. (i) and (ii), we get
`a+2(lamda a-3c)=tc`
`implies (a-6c)=tc-2lamda a`
on comparing the coefficient of a and c, we get
`1=-2lamda implies lamda=-(1)/(3)`
and `-6=t implies t=-6`.
From eq. (i) we get,
`a+2b=-6c` ,brgt `implies a+2b+6c=0`
Promotional Banner

Similar Questions

Explore conceptually related problems

Let veca, vecb, vecc be three non-zero vectors, which are pair-wise non-collinear. If veca+ 3 vecb is collinear with c and vecb + 2 vecc is collinear with veca, then veca + 3 vecb + 6 vecc is :

Let veca , vecb,vecc be three non zero vectors which are pair wise non collinear and veca+vec3b is colinear with vecc and vecb+vec2c is colinear with veca then veca+3b+6vecc is

Let veca, vecb, and vecc be three non-zero vectors such that no two of them are colinear and (veca xx vecb) xx vecc=1/3 |vecb||vecc|veca. If theta is the angle between the vectors vecb and vecc, then a value of sin theta is :

Let veca,vecb and vec c be three non zero vectors such that no two of them are collinear and (vec a xx vec b) xx vec c=1/3 |vecb||vecc|veca if theta the angle between the vectors vecb and vec c then a value of sin theta is

If veca, vecb, vecc are three non-zero vector such that each one of then is perpendicular to the sum of the other two vectors, then the value of |veca+vecb+vecc|^(2) is :

If veca , vecb,vecc are three non zero vectors such that each one of then is perpendicular to the sum of the other two vectors then the value of |veca+vecb+vecc|^(2) is

Let veca, vecb and vecc be non-zero vectors such that (veca xx vecb) xx vecc=1/3|vecb||vecc|veca. If theta is the acute angle between the vectors vecb and vecc, then sin theta equals.

If non-zero vectors veca and vecb are equally inclined to coplanar vector vecc , then vecc can be

If veca,vecb and vecc are unit vectors such that veca+vecb+vecc=vec0 then angle between veca and vecb is