COMEDK2025MathematicsThree Dimensional GeometryActual
The equation of a line passing through origin with direction angles 2 3 , 4 , 3 is
Options
- Ax= y 2 =z
- Bx -1 = y - 2 =z
- Cx= y - 2 =z
- Dx= y - 2 =-z
Correct answer
D. x= y - 2 =-z
Step-by-step solution
The direction angles of the line are given as = 2 3 , = 4 , and = 3 . The direction cosines of the line are l = , m = , and n = . Calculating these values: l = ( 2 3 ) = - 1 2 m = ( 4 ) = 1 2 n = ( 3 ) = 1 2 The equation of a line passing through the origin (0, 0, 0) with direction cosines (l, m, n) is given by x l = y m = z n . Substituting the values: x -1/2 = y 1/ 2 = z 1/2 Multiplying the denominators by 2 : x -1 = y 2 = z 1 This can be rewritten as: -x = y 2 = z Multiplying by -1 : x = y - 2 = -z Answer: x= y