StreakPeaked· Practice

ExamsJEE MainMaths

Which one of the following lines cannot be a normal to the parabola x² = 4y?

  1. x - y + 3 = 0
  2. x + y - 3 = 0
  3. x - 2y + 12 = 0
  4. x + 2y + 12 = 0

Correct answer: x - 2y + 12 = 0

Solution

The normal to x² = 4y has equation x + ty = 2t + t³ (at parameter t). Testing the lines, x - 2y + 12 = 0 cannot be expressed in normal form for any real t.

Related JEE Main Maths questions

⚔️ Practice JEE Main Maths free + battle 1v1 →