Question

The equations of the line passing through the point $(1,2,3)$ having the direction ratios $3,2,1$ are

• A. $\frac{x-1}{3}=\frac{y-2}{2}=\frac{z-3}{1}$
• B. $\frac{x}{3}=\frac{y}{6}=\frac{z}{9}$
• C. $\frac{x+2}{3}=\frac{y}{2}=\frac{z-2}{1}$
• D. none of these

Answer 1

The correct option is A $\frac{x-1}{3}=\frac{y-2}{2}=\frac{z-3}{1}$

As line has direction ratio $(3,2,1)$. It is parallel to $3\hat{i}+2\hat{j}+\hat{k}$.

As line passes there $(1,2,3)$

$\frac{x-1}{3}=\frac{y-2}{2}=\frac{z-3}{1}$

Hence, option $A$ is the correct answer.