Form the differential equation of the family of hyperbolas having foci on the x-axis and centers at the origin.
Equation of the family of an ellipse having foci on the y-axis and centers at the origin can be represented by
 (1)
 (1)
Differentiating the above equation with respect to x on both sides, we have,




Again differentiating the above equation with respect to x on both sides, we have,


Rearranging the above equation

This is the required differential equation.