Prove that the lines whose directioncosines are given by the equtions `l+m+n=0 and 3lm-5mn+2nl=0` are mutually perpendicular.

Prove that the lines whose direction cosines are given by the equations l+m+n=0 and 3lm-5mn+2nl=0 are mutually perpendicular.

The pair of lines whose direction cosines are given by the equations 3l+m+5n=0 and 6mn-2nl+5lm=0 are a.parallel b.perpendicular c.inclined at cos^(-1)((1)/(6)) d.none of these

Find the angle between the lines whose direction cosines are given by the equations 3l+m+5n=0 and 6mn-2nl+5lm=0

Find the angle between the lines whose direction cosines are given by the equations 3l+m+5n=0,6mm-2nl+5l=0

The angle between the lines whose direction cosines are given by the equatios l^2+m^2-n^2=0, m+n+l=0 is

The angle between the lines whose directionn cosines are given by 2l-m+2n=0, lm+mn+nl=0 is

The angle between the straight lines, whose direction cosines are given by the equations 2l+2m -n=0 and mn+nl+lm=0 , is :

An angle between the lines whose direction cosines are given by the equations, 1+ 3m + 5n =0 and 5 lm - 2m n + 6 nl =0, is :