MathDB
Putnam 2018 A3

Source:

December 2, 2018
PutnamPutnam 2018

Problem Statement

Determine the greatest possible value of i=110cos(3xi)\sum_{i = 1}^{10} \cos(3x_i) for real numbers x1,x2,,x10x_1, x_2, \dots, x_{10} satisfying i=110cos(xi)=0\sum_{i = 1}^{10} \cos(x_i) = 0.