Minimize the sum of difference squares
Source: KJMO 2018 p6
July 26, 2019
algebra
Problem Statement
Let there be a figure with disks and edges, as shown below.We will write a real number in each and every disk. Then, for each edge, we will write the square of the difference between the two real numbers written in the two disks that the edge connects. We must write in disk , and in disk . Find the minimum sum of all real numbers written in edges.