The Sobolev space $H^s(\mathbb R^n)$ is closed under multiplication when $s>n/2$
33397
Sobolev space $H^s(\mathbb{R}^n)$ is an algebra with $2s>n$
64764
Sign of Laplacian at critical points of $\mathbb R^n$
12913
space of riemann integrable functions not complete
158569
Proving a particular subset of $R^n$ is closed
135814
Prove certain subsets of $\mathbb R^n$ are subspaces
102284
$GL(n,\mathbb R)/SL(n,\mathbb R)$ is isomophic to $\mathbb R^\times$
62971
About smooth approximation in a Sobolev space
37206
$\mathbb{R}^n\times\{0\}$ has measure zero in $\mathbb{R}^{n+1}$
134065
A question about an $n$-dimensional subspace of $\mathbb{F}^{S}$.
99675
A closed ball in $l^{\infty}$ is not compact
11259
Prove $R\times S$ is not an integral domain
42883
Cross product in $\mathbb R^n$
65162
Show that $\dim H^0(\mathbb{P}^n, \mathcal{O}_{\mathbb{P}^n}(m)) = {n + m \choose n}$ if $m \geq 0$, and $0$ otherwise.
56433
Volume form on $(n-1)$-sphere $S^{n-1}$
95074
Separability of $l^{p}$ spaces
42494
The boundary is a closed set
143105
Show that, for every real number a, the set {$x ∈ S | f(x) ≤ a$} is a closed subset of $\mathbb R^d$