Class 12MathematicsTHREE DIMENSIONAL GEOMETRYSystem of co-ordinates, Direction cosines and direction ratios, Projection
EasyIf a line makes angles $\alpha, \beta, \gamma$ with the positive direction of $x, y$ and $z$-axis respectively,then $\cos^2 \alpha + \cos^2 \beta + \cos^2 \gamma$ is equal to:
- A$1/2$
- B$-1/2$
- C$-1$
- D$1$
Explore More
Similar Questions
The angle between the lines whose direction ratios satisfy the equations $l+m+n=0$ and $l^2=m^2+n^2$ is
The angle between the lines whose direction cosines $(\ell, m, n)$ satisfy the equations $\ell+m+n=0$ and $\ell^2+m^2-n^2=0$ is:
If the direction cosines of two lines are such that $l+m+n=0$ and $l^2+m^2-n^2=0$, then the angle between them is
DifficultAP EAMCET 2009
View SolutionIf the angle between the lines whose direction ratios are $2, -1, 2$ and $a, 3, 5$ is $45^\circ$,then $a =$
Easy
View SolutionVedclass 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