Let be the angle between the lines whose direction cosines satisfy the equations l+m-n=0 and l^2+m^2-n^2=0....

Question

Let be the angle between the lines whose direction cosines satisfy the equations l+m-n=0 and l^2+m^2-n^2=0. Then the value of ^4 + ^4 is :

Accepted Answer

(C)

JEE Main 2021 Mathematics question