NTA Abhyas JEE Main2020MathematicsParabolaPractice
The locus of the trisection point of any arbitrary double ordinate of the parabola x 2 = 4 y , is
Options
- A9 x 2 = y
- B3 x 2 = 2 y
- C9 x 2 = 4 y
- D9 x 2 = 2 y
Correct answer
C. 9 x 2 = 4 y
Step-by-step solution
Let A ≡ 2 t , t 2 , B ≡ - 2 t , t 2 be the extremities on the double ordinate A B . Let C h , k be it’s trisection point, then 6 h = 4 t and k = t 2 ⇒ t = 3 h 2 , t 2 = k ⇒ k = 9 h 2 4 Thus, locus of C is 9 x 2 = 4 y