Question

The position vector of a point which is $2$ units away from $3\hat{i}+4\hat{j}+2\hat{k}$ along the $x$-axis is:

• A. $\hat{i}+4\hat{j}+2\hat{k}$
• B. $3\hat{i}+2\hat{j}+2\hat{k}$
• C. $5\hat{i}+4\hat{j}+2\hat{k}$
• D. $3\hat{i}+4\hat{j}+\hat{k}$

Answer 1

Answer: (A), (C)

The correct options are
A $\hat{i}+4\hat{j}+2\hat{k}$
C $5\hat{i}+4\hat{j}+2\hat{k}$

A vector that starts from the origin (O) is called a position vector.

Consider the above image:

in the given equation $3\hat{i}+4\hat{j}+2\hat{k}$ ......(1)

we have to take away 2 units along x axis it may be left of thea xis or right of the axis , hence this question have 2 answers:

1) $\hat{i}+4\hat{j}+2\hat{k}$ $\Rightarrow$ When 2units (left) away form eqn (1)

2) $5\hat{i}+4\hat{j}+2\hat{k}$ $\Rightarrow$ When 2units (right) away form eqn (1).