By Theorem \(\PageIndex{1}\), if \(h'(\mathtt{x}_0,\ldots,\mathtt{x}_{r-1})\neq h'(\mathtt{y}_0,\ldots,\mathtt{y}_{r-1})\), then \(\Pr\{h(\mathtt{x}_0,\ldots,\mathtt{x}_{r-1}) = h(\mathtt{y}_0,\ldots,...By Theorem \(\PageIndex{1}\), if \(h'(\mathtt{x}_0,\ldots,\mathtt{x}_{r-1})\neq h'(\mathtt{y}_0,\ldots,\mathtt{y}_{r-1})\), then \(\Pr\{h(\mathtt{x}_0,\ldots,\mathtt{x}_{r-1}) = h(\mathtt{y}_0,\ldots,\mathtt{y}_{r-1})\} \le 2/2^{\mathtt{w}}\).