Circle Inversion Mapping: Proof of w = 1/z Transforming |z-1| = 1 to x = 1/2

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Homework Statement


Show that the inversion mapping w = f(z) = 1/z maps the circle |z - 1| = 1 onto the vertical line x = 1/2.


Homework Equations





The Attempt at a Solution


z = a + ib
w = x + yi = a^2/(a^2 + b^2) + ib^2/(a^2 + b^2)
|z - 1| = |(a -1) + ib | = 1
(a - 1)^2 + b^2 = 1
a^2 + b^2 = 2ab

Not sure what to do afterwards.
 
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Hint: The last equation is wrong. It should read a^2+b^2=2a, which makes your job a whole lot easier.
 
Thanks! That was really easy.
 
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