Question 28
Consider the set of all equations $x^3+a_2x^2+a_1x+a_0=0,$ where $a_2,$ $a_1,$ $a_0$ are real constants and $|a_i|\le2$ for $i=0,$ $1,$ $2.$ Let $r$ be the largest positive real number which satisfies at least one of these equations. Then