MathDB
Casey variable modulus expression

Source: Romanian District Olympiad, Grade X, Problem 3

October 5, 2018
complex numbersalgebra

Problem Statement

Let α,β \alpha ,\beta be real numbers. Find the greatest value of the expression αx+βy+αxβy |\alpha x +\beta y| +|\alpha x-\beta y| in each of the following cases:
a) x,yR x,y\in \mathbb{R} and x,y1 |x|,|y|\le 1 b) x,yC x,y\in \mathbb{C} and x,y1 |x|,|y|\le 1