Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Observe the following facts for a parabola :
(i) Axis of the parabola is the only line which can be the perpendicular bisector of the two chords of the parabola.
(ii) If $AB$ and $CD$ are two parallel chords of the parabola and the normals at $A$ and $B$ intersect at $P$ and the normals at $C$ and $D$ intersect at $Q$, then $PQ$ is a normal to the parabola.
Let a parabola is passing through $(0,1),(-1,3),(3,3)$ & $(2,1)$
The vertex of the parabola is -

Conic Sections

Solution:

Axis of parabola is bisector of parallel chord A B $\& CD$ are parallel chord.
so axis $x =1$
image
equation of parabola is
$(x-1)^2=a y+b$
It passing $(0,1) \&(3,3)$
so $1= a + b$...(1)
$4=3 a+b$...(2)
from (1) & (2)
$a=\frac{3}{2} \& b=-\frac{1}{2}$
$(x-1)^2=\frac{3}{2}\left(y-\frac{1}{3}\right)$
Vertex $\left(1, \frac{1}{3}\right)$