" If "l,m,n" are three lines such that "l|m" and "n perp l" ,prove that "n perp m

If l,n are three lines such that lm and n perp l prove that n perp m.

If l ,\ m,\n are three lines such that l || m\ a n d\ n_|_l , prove that n_|_mdot

If l,m and n are three straight lines such that l||m and l||n then prove that m||n .

Prove that l||m||n

If l,m,n are direction cosines of the line then -l,-m,-n can be

n,l,m are three lines in the same plane.If l intersects m and nllm, then find the relation betweenl and n.

If l_(1), m_(1), n_(1) and l_(2), m_(2), n_(2) are the direction cosines of two lines and l , m, n are the direction cosines of a line perpendicular to the given two lines, then

Two lines l and m interset at the O and P is Point on a line n Passing through the point O such that P is equidistant from l and m. Prove that n is the bisectof the angle formed by l and m

Two lines l and m interset at the O and P is Point on a line n Passing through the point O such that P is equidistant from l and m. Prove that n is the bisectof the angle formed by l and m

If the direction cosines of a straight line are l,m and n, then prove that l^(2)+m^(2)+n^(2)=1