Is $\mathbb{R}^2$ a polyhedron?
110353
Is $\mathbb{R}^n$ a polyhedron?
12764
$\Bbb RP^2$ as the union of a Möbius band and a disc
2575
Showing that $\mathbb{R}$ is connected
148101
Basis for $\mathbb{Z}^2$
23851
Is there a set of lines in $\mathbb{R}^3$ such that their union is equal to the set of points with not all coordinates rational?
67374
Is it true that $\mathbb{R}$ and $\mathbb{R}^2$ are isomorphic as abelian groups?
69166
Cardinality of $\mathbb{R}$ and $\mathbb{R}^2$
22959
Does every even-dimensional sphere admit an almost complex structure?
60684
Determine whether the set $W$ is a subspace in $\mathbb{R}^{3}$
19754
$\mathbb{R}$ \ $\mathbb{Q}$ and $\mathbb{R}^2\setminus\mathbb{Q}^2$ disconnected?
96567
Immersion of $\mathbb{R}$ to $\mathbb{R}^2$
67244
Why is $L^1(\mathbb{R}^n) \cap L^2(\mathbb{R}^n)$ dense in $ L^2(\mathbb{R}^n)$?
84189
Is $\mathbb{C}$ equal to $\mathbb{R}^2$?
2348
Show that the sphere, S, and $\mathbb{R}^2$ is not homeomorphic
115270
What are the generators of $(\mathbb{R},+)$?
76937
Is there an elementary way to see that there is only one complex manifold structure on $R^2$?
16860
set of almost complex structures on $\mathbb R^4$ as two disjoint spheres