The acute angle between the two lines whose `d.cs` are given by `l+m-n=0` and `l^(2)+m^(2)-n^(2)=0` is

The angle between the lines whose direction cosines are given by 3l+4m+5n=0 , l^(2)+m^(2)-n^(2)=0 is

The angle between the lines whose does are given by the equation l^(2)+m^(2)-n^(2)=0,l+m+n=0 is

Find the angle between the line whose direction cosines are given by l+m+n=0 and 2l^(2)+2m^(2)-n^(2)-0

Find the acute angle between the two straight lines whose direction cosines are given by l+m+n=0 and l^(2)+m^(2)-n^(2)=0

Find the angle between the lines whose direction cosines has the relation l+m+n=0 and 2l^(2)+2m^(2)-n^(2)=0 .

Find the angle between the lines whose direction-cosines are given by : (i) l + m + n = 0, l^(2) + m^(2) - n^(2) = 0 (ii) 2l - m + 2n = 0 , mn + nl + lm = 0 ,