Question

If the position vectors of the points A and B be $2\mathbf{i} + 3\mathbf{j} - \mathbf{k}$ and $- 2\mathbf{i} + 3\mathbf{j} + 4\mathbf{k},$ then the line AB is parallel to

• A. xy-plane
• B. yz-plane
• C. zx-plane
• D. None of these

Answer 1

Answer: (C)

zx-plane

Answer 2

$\overset{\rightarrow}{AB} = - 4\mathbf{i} + 5\mathbf{k}$, which is a vector lying in a plane parallel to $xz -$plane.