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5:42 AM
Q: Why does the Newman/Zagier proof of the PNT invoke complex analysis?

user361424I was thinking, specifically, of this paper, in which Zagier offers a proof of the PNT, inspired by a paper of Newman's, the Cliffs Notes version of which would be that, first, it's fairly easy to show that $$\left|\int_1^{\infty}\frac{\vartheta(x) - x}{x^2}dx\right| < \infty \implies \vartheta(...

Q: Number of solutions for $x^3+ax^2+b$

Lost1Sketch the curve $\mathrm{f}(x)=x^{3}+Ax^{2}+B$ first in the case $A>0$ and $B>0$, and then in the case $A<0$ and $B>0.$ Show that the equation $x^{3}+ax^{2}+b=0$, where $a$ and $b$ are real, will have three distinct real roots if $27b^{2}+3a^{3}b<0,$ but will have fewer than three if $27b^{...

Q: Group of monomial functions over a group.

Fruitful ApproachDefine a monomial function $f: G \to G$ to be a function that can be written in the form $f(x) = g x g'$ for some $g, g' \in G$. Let $G$ be a finite group and consider the set of $S$ of all monomial functions from $G$ to $G$ that take one argument. For instance $(f(x) = abxcd) \in S$. Now if $...

7 hours later…
12:27 PM
Also among [new tags]: and . Probably both of them created in the same question.
Q: diffeomorphism and fixed points and periodic points

UrgentCould anyone help me to solve the following? $f:[0,1]\to[0,1]$ be a diffeomorphism, I need to show (1) $f'(x)>0\Rightarrow $ it has only fixed points but no periodic points. (2) $f'(x)<0\Rightarrow $ it has unique fixed point, periodic points has period two if there is any. Thanks.

Q: when can a function serve as its own correction for finding its roots via an iteration function? what is it called in this case?

crowWhat are the criteria such that a function $f(t)$ can serve as the correction in an iteration function of the form $g (t) = t - \lambda f (t)$ where $\lambda$ is some relaxation factor? It is almost reminiscent of Newton's iteration, without the derivative. for instance, if $f(t)=sin(t)$ then $g...

We already have a few tags related to fixed points: , and .

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