Midcircle

$\begin{figure}\begin{center}\BoxedEPSF{Midcircle.epsf scaled 800}\end{center}\end{figure}$

The midcircle of two given Circles is the Circle which would Invert the circles into each other. Dixon (1991) gives constructions for the midcircle for four of the five possible configurations. In the case of the two given Circles tangent to each other, there are two midcircles.

See also Inversion, Inversion Circle

References

Dixon, R. Mathographics. New York: Dover, pp. 66-68, 1991.