The pair of lines whose direction cosines are given by the equations `3l+m+5n=0a n d6m n-2n l+5l m=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 connected by the relations l+m+n=0a n d2lm+2n l-m n=0.

Find the angle between the line whose direction cosines are given by l+m+n=0a n d2l^2+2m^2-n^2-0.

Show that the straight lines whose direction cosines are given by the equations al+bm+cn=0 and u l^2+z m^2=v n^2+w n^2=0 are parallel or perpendicular as a^2/u+b^2/v+c^2/w=0 or a^2(v +w)+b^2(w+u)+c^2(u+v)=0

If 1/2,1/3,n are the direction cosines of a line , then the value of n is

If 1/2, 1/3, n are the direction cosines of a line , then the values of n is

The direction cosines of a line satisfy the relations lambda(l+m)=n and m n+n l+l m=0. The value of lambda, for which the two lines are perpendicular to each other, is

The direction cosines of two lines are connected by relation l+m+n=0 and 4l is the harmonic mean between m and n. Then,

If l ,m ,n are real l!=m , then the roots of the equation (l-m)x^2-5(l_+m)x-2(l-m)=0 are a. real and equal b. Complex c. real and unequal d. none of these

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