Question

The plane XOZ divides the join of $(1, -1, 5)$ and $(2, 3, 4)$ in the ratio $\lambda :1$ then $\lambda$ is

• A. -3
• B. $- \frac {1} {3}$
• C. 3
• D. $\frac {1} {3}$

Answer 1

Answer: (D)

$\frac {1} {3}$

Answer 2

Sine $ZOX$ plane $i.e., \, y$ = 0 divide the join of (1, -1, 5) and (2, 3, 4) in the ratio $\lambda$ : 1. $\therefore$ $\frac{3 \lambda - 1}{\lambda +1}$ = 0 $\Rightarrow \, \lambda = \frac{1}{3}$