[" If two parallel straight lines have direction cosines "l_(1),m_(1),n_(1)" and "L_(2),m_(2),n_(2)],[" then "]

Two lines with direction cosines l_(1),m_(1),n_(1) and l_(2), m_(2), n_(2) are at right angle of

The direction cosines of the lines bisecting the angle between the lines whose direction cosines are l_(1),m_(1),n_(1) and l_(2),m_(2),n_(2) and the angle between these lines is theta, are

Find the direction ratios of the line bisecting the angles between the lines whose direction cosines are l_(1), m_(1), n_(1) and l_(2), m_(2), n_(2) and the angle between the lines is theta .

If three mutually perpendicular lines have direction cosines (l_(1),m_(1),n_(1)),(l_(2),m_(2),n_(2)) and (L_(3),m_(3),n_(3)) then the line having direction cosines l_(1)+l_(2)+l_(3),m_(1)+m_(2)+m_(3), and n_(1)+n_(2)+n_(3) ,make an angle of

The direction cosines of a line equally inclined to three mutually perpendiclar lines having direction cosines as l_(1),m_(1),n_(1),l_(2),m_(2),n_(2) and l_(3), m_(3),n_(3) are

The direction cosines of a line equally inclined to three mutually perpendiclar lines having direction cosines as l_(1),m_(1),n_(1),l_(2),m_(2),n_(2) and l_(3), m_(3),n_(3) are

The direction cosines of a line equally inclined to three mutually perpendiclar lines having direction cosines as l_(1),m_(1),n_(1),l_(2),m_(2),n_(2) and l_(3), m_(3),n_(3) are

The direction cosines of a line equally inclined to three mutually perpendiclar lines having direction cosines as l_(1),m_(1),n_(1),l_(2),m_(2),n_(2) and l_(3), m_(3),n_(3) are

If theta is the acute angle between two intersecting straight lines, one having direction cosines l_(1),m_(1),n_(1) and the other having direction cosines l_(2),m_(2),n_(2) then sin^(2)theta =