# Hatcher 2.1.3

Hatcher, Algebraic Topology, Chapter 2, Section 1

3. Construct a $\Delta$-complex structure on $\mathbb{R}P^n$ as a quotient of a $\Delta$-complex structure on $S^n$ having vertices the two vectors of length 1 along each coordinate axis in $\mathbb{R}^{n+1}$.
Proof.

$\square$