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Sequence of quadratic equations

Source: Brazilian Mathematical Olympiad 2024, Level 2, Problem 5

October 12, 2024
algebraquadraticsboardSequence

Problem Statement

Esmeralda chooses two distinct positive integers aa and bb, with b>ab > a, and writes the equation
x2ax+b=0 x^2 - ax + b = 0
on the board. If the equation has distinct positive integer roots cc and dd, with d>cd > c, she writes the equation
x2cx+d=0 x^2 - cx + d = 0
on the board. She repeats the procedure as long as she obtains distinct positive integer roots. If she writes an equation for which this does not occur, she stops.
a) Show that Esmeralda can choose aa and bb such that she will write exactly 2024 equations on the board. b) What is the maximum number of equations she can write knowing that one of the initially chosen numbers is 2024?