Problem
GEO-B2-M05-P004 A Concentric Circle
#4
★★☆☆☆ Level 2 of 5
An inversion has centre \(O\) and radius \(12\). What is the image of the circle with centre \(O\) and radius \(3\)?
For every point of the circle, the distance to \(O\) is \(3\).
If \(P\) lies on the circle, then \(OP=3\). Then \(3\cdot OP'=144\), so \(OP'=48\). The image is the circle with centre \(O\) and radius \(48\).
A simple model for the image of a circle.