Class 12MathematicsTHREE DIMENSIONAL GEOMETRYSystem of co-ordinates, Direction cosines and direction ratios, Projection
EasyIf $< a, b, c >$ and $< a', b', c' >$ are the direction ratios of two perpendicular lines,then which of the following is true?
- A$a/a' = b/b' = c/c'$
- B$aa' + bb' + cc' = 0$
- C$aa' + bb' + cc' = 1$
- DNone of these
Explore More
Similar Questions
The angle between the lines with direction ratios $(2, -2, 1)$ and $(1, -2, 2)$ is
$A$ straight line is equally inclined to all the three coordinate axes. Then,the angle made by the line with the $y$-axis is
The direction cosines of the line $\frac{3x + 1}{-3} = \frac{3y + 2}{6} = \frac{z}{-1}$ are
Easy
View SolutionThe acute angle between the lines whose direction cosines are given by the equations $l+m+n=0$ and $2lm+2ln-mn=0$ is
DifficultAP EAMCET 2018
View SolutionIf the direction cosines of two lines satisfy the equations $2l+m-n=0$ and $l^2-2m^2+n^2=0$, and $\theta$ is the angle between the lines, then $\cos \theta=$
Vedclass Products
For Students
Vedclass Test Series
Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Live online exams with unlimited students, 360° analytics & white-label branding.
See Demo