Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Three-dimensional Geometry

Question:

The direction cosines of a line which makes equal angles with the coordinate axes are

Options:

\(\frac{1}{2},\frac{1}{2},\frac{1}{2}\)

\(\pm \frac{1}{\sqrt{3}},\pm \frac{1}{\sqrt{3}},\pm \frac{1}{\sqrt{3}}\)

\(\pm \frac{1}{\sqrt{2}},\pm \frac{1}{\sqrt{2}},\pm \frac{1}{\sqrt{2}}\)

\(1,1,1\)

Correct Answer:

\(\pm \frac{1}{\sqrt{3}},\pm \frac{1}{\sqrt{3}},\pm \frac{1}{\sqrt{3}}\)

Explanation:

\(\cos^2 \alpha+\cos^2 \alpha+\cos^2 \alpha=1\)