Why is the product map $GL_1(k)\times GL_1(k)\rightarrow GL_1(k)$ not continuous?
92298
The additive group $\mathbb{G}_a$ over an infinite field $k$ is not a topological group
2198
Maps from subsets of $\mathbb{R}^2$ that are either open/closed/continuous
7418
The Center of $\operatorname{GL}(n,k)$
75479
Proving that this function is continuous on $G\times G$
130916
Proving the identity functions is continuous iff $\tau_1\supseteq\tau_2$
91777
Product of Non-Disjoint Cycles
93606
Showing that $C[0,1]$ is not complete
72115
Why isn't there a continuously differentiable surjection from $I \to I \times I$?
147788
Why is every map to an indiscrete space continuous?
72044
prove $x \mapsto x^2$ is continuous
46788
Compact open topology on space of continuous maps from a discrete space is a product
64619
Continuity of a function of product spaces
80100
Boundary of product manifolds such as $S^2 \times \mathbb R$
158349
Prove the map sending a matrix to it's inverse is continuous.
101319
Properties of a continuous map $f : \mathbb{R}^2\rightarrow \mathbb{R}$ with only finitely many zeroes
6161
The cartesian product $\mathbb{N} \times \mathbb{N}$ is countable
142174
Nonexistence of an injective $C^1$ map between $\mathbb R^2$ and $\mathbb R$