A classic functional equation solution using injectivity

In this video, we present a solution to Belarus MO 2019/7. 00:00 Problem Statement 00:31 Solution Check out our website https://www.calimath.org to find past problems, solutions and other cool stuff. Solution PDF: https://calimath.org/pdf/BelarusMO2019-7.pdf branch: algebra difficulty: 7 Our website: https://www.calimath.org Contact us: [email protected]