MathDB
2021 Individual Tiebreaker #2

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October 5, 2022
2021Individual Tiebreaker

Problem Statement

For a real number x,x, let x\lfloor x\rfloor denote the greatest integer less than or equal to x,x, and let {x}=xx\{x\} = x -\lfloor x\rfloor denote the fractional part of x.x. The sum of all real numbers α\alpha that satisfy the equation α2+{α}=21\alpha^2+\{\alpha\}=21 can be expressed in the form abcd\frac{\sqrt{a}-\sqrt{b}}{c}-d where a,b,c,a, b, c, and dd are positive integers, and aa and bb are not divisible by the square of any prime. Compute a+b+c+d.a + b + c + d.