6TOGE Topology and Geometry, winter semester 2020/2021

HOMEWORKS

Homework 8 (0.5 points) ([V], 5.2(3)).
Describe the topological structure induced on the 2-element set \(\{1,2\}\) by the topology \(\mathbb R_{T_1}\) (recall that \(\mathbb R_{T_1}\) is the topology on \(\mathbb R\) whose open sets are the empty set and complements to all finite subsets of \(\mathbb R\)).

Homework 12 (1 point).
Give an example of a topological space \(X\) with a non-discrete topology, and equivalence relation \(S\) on it, such that the quotient \(X / S \) is a discrete topological space.

Homework 13 (1 point).
Let \(\ell_1, \ell_2\) be two lines in \(\mathbb R^2\). How many homotopically nonequivalent paths are there in the space \(\mathbb R^2 \backslash (\ell_1 \cup \ell_2)\)?


Created: Fri Nov 13 2020
Last modified: Tue Sep 24 17:41:46 CEST 2024