Prove that no such $f$ exists
28620
Function $f(z)$ such that $|f(z)| > |z|$ for every $z\in\mathbb{C}, 1/f(z)$
66951
Proving the existence of a sequence of functions converging to 0 with an added property
12272
Why $a$ is not an essential singularity and how $f$ can be extended
28452
Statement that is provable in $ZFC+CH$ yet unprovable in $ZFC+\lnot CH$
145573
How to show that $f$ is a zero function?
1821
Proving $f(C) \setminus f(D) \subseteq f(C \setminus D)$ and disproving equality
64381
Prove that if one of $\lim_{x \rightarrow 0 }{f(x)}$ and $\lim_{x \rightarrow 0}{f(x^3)}$ exists, then the other one also exists.
139744
For a continuous function $f$ show $\exists c\in (0,1)$ s.t $f(c)=3c^2$
87027
There is no continuous injective function $f:\mathbb{R}^n\longrightarrow\mathbb{R}^m$
55492
Existence of $f'\in F$ such that $f^{[G:F]}=(f')^n$ for finite extension $F\subset G$
151984
Proving the existence of a metric space
98377
How can I prove this limit doesn't exist?
91786
Proving and disproving $\exists b,c\in \mathbb R$ such that $f(x)=\frac a2x^2+bx+c $
67291
Prove that there exists $n\in\mathbb{N}$ such that $f^{(n)}$ has at least n+1 zeros on $(-1,1)$
6535
Proof of for-all / there-exists "negation"?
98356
There does not exist an entire function which satisfies $f({1\over n})={1\over 2^n}$?
154230
In $\mathsf{ZF}$, for each set $A$ exists an ordinal $\alpha$ such that no surjection $A\to \alpha$ exists