CGPET 2015 Solved Paper

Given equation is,
b2x2+y2
⇒

x2

a2

+

y2

a2b2

=1 ....(i)
Above equation of an ellipse with semi-major axis (a) and semi - minor axis (ab).
e=1−

a2b2

a2

⇒b2=1−e2 ...(ii)
Let (x,y) be extrimites of latusrectum, then
x=ae‌and‌y=±

a2b2

a2

⇒

x

a

=e‌and‌

y

a

=±b2
From Eq. (ii), we get
±

y

a

=1−

x2

a2

⇒±ay+x2=a2
Hence, locus of latusrectum is x2±ay=a2.