A particle is moving in the x y -plane along a curve C passing through the point 3 , 3 . The tangent to the…

A particle is moving in the xy-plane along a curve C passing through the point 3,3. The tangent to the curve C at the point P meets the x-axis at Q. If the y-axis bisects the segment PQ, then C is a parabola with
  1. length of latus rectum 3
  2. length of latus rectum 6
  3. focus 43,0
  4. focus 0,33

Solution

Let Point Px,y

So equation of line passing through Px,y will be

 Y-y=mX-x

Point on x-axis is given by Qx-ym,0

Mid-point of PQ lies on y axis so its x co-ordinate will be zero,

x-ym+x=0

m=y2·x2dyy=dxx

2lnn=lnx+lnk

y2=kx

It passes through 3,3k=3

curve cy2=3x

Length of L.R. =3

Focus=34,0

Asked in: JEE Main 2022 (24 Jun Shift 2)

Practice more Parabola questions on Aicharya