Analytic mapping of unit disc onto itself with two fixed pts.

d2j2003
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Homework Statement



let f(z) be a 1-1 analytic mapping of unit disc |z|<1 onto itself with two fixed points in |z|<1 Show that f(z)=z


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The Attempt at a Solution



I'm thinking there has to be a theorem or something that I am missing for this.. But I'm not really sure where to get started..

To start, let a and b be the two fixed points in |z|<1, then f(a)=a and f(b)=b and I am sure there is a way to show that the only function that does this is f(z)=z not sure how though...
 
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Try thinking about the Schwarz lemma.
 
Got it, Thanks!
 
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