JEE PYQ: Parabola Question 1
Question 1 - 2021 (16 Mar Shift 1)
If the three normals drawn to the parabola, $y^2 = 2x$ pass through the point $(a, 0)$, $a \neq 0$, then ‘a’ must be greater than:
(1) $\frac{1}{2}$
(2) $-\frac{1}{2}$
(3) $-1$
(4) $1$
Show Answer
Answer: (4)
Solution
For standard parabola, for more than 3 normals on axis: $x > \frac{L}{2}$ where $L$ is the length of latus rectum. For $y^2 = 2x$, L.R. $= 2$. So $a > \frac{L.R.}{2} = 1 \Rightarrow a > 1$.
BETA
