2
Part of 2005 Pan African
Problems(2)
Integer set and polynomial
Source: Pan African Maths Olympiad
8/11/2005
Let be a set of integers with the property that any integer root of any non-zero polynomial with coefficients in also belongs to . If and are elements of , prove that is also an element of .
algebrapolynomial
Animal and Cage
Source: Pan African Maths Olympiad
8/11/2005
Noah has to fit 8 species of animals into 4 cages of the Arc. He planes to put two species of animal in each cage. It turns out that, for each species of animal, there are at most 3 other species with which it cannot share a cage. Prove that there is a way to assign the animals to the cages so that each species shares a cage with a compatible species.
Euleralgorithmunsolved