MathDB
g: lines -> points, L_3 connects g(L_1), g(L_2) => g(L_3) is their intersection

Source: SMMC 2024 B3

October 12, 2024
geometry

Problem Statement

Let L\mathcal{L} be the set of all lines in the plane and let P\mathcal{P} be the set of all points in the plane. Determine whether there exists a function g:LPg : \mathcal{L} \to \mathcal{P} such that for any two distinct non-parallel lines 1,2L\ell_1, \ell_2 \in \mathcal{L}, we have (a)(a) g(1)g(2)g(\ell_1) \neq g(\ell_2), and (b)(b) if 3\ell_3 is the line passing through g(1)g(\ell_1) and g(2)g(\ell_2), then g(3)g(\ell_3) is the intersection of 1\ell_1 and 2\ell_2.