JEE Main20198 Apr 2019Morning ShiftMathematicsThree Dimensional GeometryActual
The length of the perpendicular from the point ( 2 , - 1 , 4 ) on the straight line x + 3 10 = y - 2 - 7 = z 1 is
Options
- Agreater than 3 but less than 4
- Bgreater than 4
- Cless than 2
- Dgreater than 2 but less than 3
Correct answer
A. greater than 3 but less than 4
Step-by-step solution
Let P 2 , - 1,4 Now, any point Q on line x + 3   10 = y - 2 - 7 = z 1 = λ is Q = 10 λ - 3 ,   - 7 λ + 2   , λ Direction Ratio of P Q = 10 λ - 3 - 2 ,   - 7 λ + 2 + 1 ,     λ - 4 = 10 λ - 5 ,   - 7 λ + 3 ,   λ - 4 ∵ P Q   is perpendicular to given line ∴ 10 10 λ - 5 - 7 - 7 λ + 3 +   λ - 4 = 0 ⇒ 150   λ = 75   ⇒ λ = 1 2 ∴ Q ≡ 2 , - 3 2 , 1 2 Distan