MathDB
Determinants equal mod 2

Source: ICMC 2022 Round 1 P3

December 4, 2021
linear algebracollege contestsDeterminantsICMC

Problem Statement

Let M\mathcal M be the set of n×nn\times n matrices with integer entries. Find all AMA\in\mathcal M such that det(A+B)+det(B)\det(A+B)+\det(B) is even for all BMB\in\mathcal M.
Proposed by Ethan Tan