Iteration with two analytic fixed points
#36
(08/09/2022, 12:07 PM)bo198214 Wrote: Ok, I even can give a polynomial
\[ p (x)  = x ^ 3 + \frac{\sqrt{5}-3}{2} x^2 - \frac{\sqrt{5}-3}{2} x \]

has fixed points 0 and 1 and 
\[ p'(x) = 3x^2 + (\sqrt{5}-3)x - \frac{\sqrt{5}-3}{2} \]

The derivatives at the fixed points are:
\( p'(0) = -\frac{\sqrt{5}-3}{2}, p'(1) = 3 + \frac{\sqrt{5}-3}{2}=\frac{\sqrt{5}+3}{2}\) hence 
\[ p'(0)p'(1) = -\frac{(\sqrt{5}-3)(\sqrt{5}+3)}{4} = 1\]

you got the fixpoints derivatives connection right. 

but how do you know both regulars agree ?
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Messages In This Thread
RE: Iteration with two analytic fixed points - by tommy1729 - 08/12/2022, 02:14 AM

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