Question

If $\overline{AB}=(2i+3j-k)$ and A(1, 2, -1) is the given point, then the co-ordinates of B are

• A. (3, 5, 2)
• B. (3, 5, -2)
• C. (2, 4, 1)
• D. (2, 4, -1)

Answer 1

Answer: (B)

(3, 5, -2)

Answer 2

We have:

$$\overrightarrow{AB} = \langle 2,3,-1 \rangle,\quad A=(1,2,-1)$$

Coordinates of $B$ are:

$$B = A + \overrightarrow{AB} = (1+2,\; 2+3,\; -1+(-1)) = (3,5,-2)$$

Add the given vector to point A to get the coordinates of B.