That's how it is. It's tradition to play Big Game Hunters in a 4v4 or FFA while trash talking and telling everyone they're terrible (in the worst possible language ever) and should never play again then tell any player you've defeated "LOL NOOB?"
Thick skin is a requirement for playing in online games.
If you can understand how to do prime factorization, you can prove the 2a^2 = b^2 false by showing there will always be an extra 2 on the left side (when you do the prime factorization of a^2 and b^2 and use that instead of the a^2 and b^2 notation that is) that the right side can never match.