MathDB
one zero means two zeroes

Source: Tournament of Towns,Spring 2002, Junior O Level, P3

May 13, 2014
modular arithmeticalgebrapolynomialquadraticsnumber theory proposednumber theory

Problem Statement

Show that if the last digit of the number x2+xy+y2x^2+xy+y^2 is 00 (where x,y∈Nx,y\in\mathbb{N} ) then last two digits are zero.