Find the direction cosines of the lines connected by the relations: `"l"+"m"+"n"=0"\ and\ "2"l m"+2"ln"-"m n"=0.`

Find the direction cosines of the lines, connected by the relations: l+m+n=0 and 2l m+2ln-m n=0.

Find the direction cosines of the lines, connected by the relations: l+m+n=0 and 2l m+2ln-m n=0.

Find the direction cosines of the two lines which are connected by th relations. l-5m+3n=0 and 7l^2+5m^2-3n^2=0

Find the angle between the lines whose direction cosines are connected by the relations l+m+n=0a n d2//m+2n l-m n=0.

Find the angle between the lines whose direction cosine are given by the equation: "l"+2"m"+3"n"=0" and "3"l m"-4"ln"+"m n"=0

Find the angle between the lines whose direction cosines are connected by the relations l+m+n=0a n d2lm+2n l-m n=0.

The direction cosines l, m and n of two lines are connected by the relations l+m+n=0 and lm=0 , then the angle between the lines is

Find the angle between the lines whose direction cosine are given by the equation: "l"-"m"+"n"=0" and l"^2-"m"^2-"n"^2=0

Find the angle between the lines whose direction cosine are given by the equation: "l"+"m"+"n"=0" and "l^2"+"m^2"-"n^2"=0

Find the angle between the lines whose direction cosine are given by the equation: 2"l"+2"m"-"n"=0, and "m n"+"ln"+"lm"=0