Proof of $f(x)=\sin x +x$ is Surjective
121729
Prove without using graphing calculators that $f: \mathbb R\to \mathbb R,\,f(x)=x+\sin x$ is both one-to-one, onto (bijective) function.
23617
Determine whether $f(x)={\sin x \over x}$ is uniformly continuous in $\mathbb R$
47856
$f(x)=ax+b$ for some $a,b\in\mathbb{Q}$ if $f(\mathbb{Q})\subset\mathbb{Q}$ and $f(\mathbb{R-Q})\subseteq \mathbb{R}-\mathbb{Q}$
149447
Proving $\sin (x)=\cos (90^\circ-x)$
5635
How to prove that the Frobenius endomorphism is surjective?
45792
Rigorous proof that surjectivity implies injectivity for finite sets
93102
prove that $f:X\rightarrow Y$ is surjective if and only if $f(f^{-1}(C))=C$
78698
Prove if $f$ has a right inverse function: $f\circ g=id_x$ $\iff$ $f$ is onto $Y$
49953
Proving that a function from $N\times N$ to $N$ is bijective.
72251
$g\circ f$ is Surjective and $g$ is Injective then Prove that $f$ is surjective
116732
Proving that a continuous map is surjective
73047
Proving surjectivity of $\cos(z)$ and $\sin(z)$ and find all $z : \cos(z) \in \mathbb R$ and all $z: \sin(z) \in \mathbb R$
21707
Constructing a Bijective function via an injective and surjective one.
40566
Counting surjective functions
93964
Proving that $f$ is a bijection from $N$x$N$ to $N$.
37308
Let $f:K\to K$ with $\|f(x)-f(y)\|\geq ||x-y||$ for all $x,y$. Show that equality holds and that $f$ is surjective.
120707
Proof regard to the function $ f\left(x\right)=\begin{cases} x^{2}\sin\left(\frac{1}{x^{2}}\right) & x\neq0\\ 0 & x=0 \end{cases} $