Question

The position vector of point $A$ is $(4,2,-3)$. If $p_1$ is perpendicular distance of $A$ from XY-plane and $p_2$ is perpendicular distance from Y-axis, then $p_1+p_2$ is

• A. $8$
• B. $3$
• C. $2$
• D. $7$

Answer 1

The correct option is A $8$

$p_1$ is perpendicular distance from XY-plane
$\therefore p_1=|z|=3$
$p_2$ is perpendicular distance from Y-axis
$p_2=\sqrt{x_1^2+z_1^2}=\sqrt{16+9}=5$
$\therefore p_1+p_2=8$