- #1
jimmycricket
- 116
- 2
Homework Statement
The line [tex]\{z: y=t+x\}[/tex] is mapped to a circle by the function [tex]f(z)=\frac{z-1}{1-zi}[/tex] Find the equation of this circle.
The Attempt at a Solution
One method is to find mappings of three points on the line. These points will be mapped to the circles boundary. Then find the intersection of the perpendicular bisectors of the two chords that join the 3 points to give the center of the circle. This turns out to be far too tedious and messy.
I've found another method that utilizes the "preservation of symmetric points under inversion" property but i only understand it when I'm dealing with a circle not a line as in this case.
For the circle case it goes something like this:
The center of the circle and infinity are inverse points with respect to the circle. Then the images [tex]f(center)\:\:\:and\:\:\:f(\infty)[/tex] are inverse with repect to the circle under inversion so [tex]f(\infty)[/tex] gives the center.
I'm not sure how to adjust this for the case with a line in the beginning.