Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Three-dimensional Geometry

Question:

The equation of a straight line parallel to the x-axis is given by

Options:

$\frac{x-a}{1}=\frac{y-b}{1}=\frac{z-c}{1}$

$\frac{x-a}{0}=\frac{y-b}{1}=\frac{z-c}{1}$

$\frac{x-a}{0}=\frac{y-b}{0}=\frac{z-c}{1}$

$\frac{x-a}{1}=\frac{y-b}{0}=\frac{z-c}{0}$

Correct Answer:

$\frac{x-a}{1}=\frac{y-b}{0}=\frac{z-c}{0}$

Explanation:

Equation of straight line parallel to x−axis is

$\frac{x-a}{1}=\frac{y-b}{0}=\frac{z-c}{0}$

because $l=\cos \alpha=1, m=\cos \beta=\cos \frac{\pi}{2}=0, n=\cos \gamma=0$