Question

The differential equations of all conics whose centre lie at the origin is of order:

• A. 2
• B. 3
• C. 4
• D. none

Answer 1

The correct option is B 3

Equation of all conics$:a{x}^2+2hxy+b{y}^2=1$

where $a,h,b$ are arbitrary constants

$\because$ it has $3$ arbitrary constants

$\therefore$ differential equation is of order $3$