Direction Cosines and Direction Ratios of a Line
Direction Cosines and Direction Ratios of a Line: Overview
This topic consists of various concepts like Line in 3D,Directions Cosines of a Line,Direction Cosines of a Line Joining Two Points, etc.
Important Questions on Direction Cosines and Direction Ratios of a Line
Let and be the vertices of the rhombus If the direction ratios of the diagonal are , where both are integers of minimum absolute values, then is equal to

If direction ratios of a line are and it makes and angle of with axis, then a value of is

Anuj and Tara are flying kites from their rooftops. Anuj's kite's string is represented by a straight line, given by Tara's position is at and her kite's string is perpendicular to Anuj's. Find out how far Tara is from where the kite strings intersect. Show your work.

A line makes an angle of 135° with the positive direction of the x-axis, and an angle of 300° with the positive direction of the y-axis. Which of the following could be the angle it makes with the negative direction of the z axis?

Write the direction cosines of the line, whose Cartesian equations are

If then write the direction cosines of ?

The direction ratios of a normal to the plane passing through and are

A line is inclined at an angle with the positive direction of axes respectively. If , then the maximum possible value of is equal to

If are the direction ratios of a ray passing through the point and also the mid point of the line segment joining the points and then

If are the direction ratios of a line joining the points and then the point lies on the plane

If the direction ratios of a line are , then the direction cosines of the line are

If the direction ratios of a line satisfy the relation and , then the direction cosines of the line are

The point of intersection of the line passing through and intersecting the lines , and with plane is :

A particle is at a point and then moves to the point then angle made by with positive direction of is

A line makes angles and with the diagonals of a cube, prove that

Show that the points and are collinear.

Find the direction cosines of and -axis.

Find the direction cosines of the line passing through the two points and

If a line makes angle and with the positive direction of and -axis respectively, find its direction cosines.

Find the direction cosines of the following line:
