Definition of a circle
A circle is defined as the locus of a point that moves in a plane such that its distance from the fixed point in that plane is always constant.
For a circle, as given earlier, e = 0. The directrix is at infinity.
∴ CP = a
where P is the locus given by (x,y), “a” is the radius of the circle and C is the center and the focus of the circle.
Example 1
Find the equation of a circle whose center is (-2 -3) and radius is 4.
Example 2
Find the center and radius of the circle whose equation is :
Try these questions
- Find the equation of a circle whose radius is 3 and origin is at the center.
- Find the center and radius of the circle whose equation is:
