Question

The plane XOZ divides the join of (1, -1, 5) and (2, 3, 4) in the ratio $\lambda :1$ then $\lambda$ is [JET 1988]

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

Answer 1

The correct option is D

$\frac{1}{3}$

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