$\underset{x\to {{1}^{+}}}{\mathop{\lim }}\,\frac{\sqrt{x}-1}{{{(x-1)}^{2}}({{x}^{2}}-5x+2)}=\underset{x\to {{1}^{+}}}{\mathop{\lim }}\,\frac{\sqrt{x}-1}{(x-1)(x+1)({{x}^{2}}-5x+2)}=\underset{x\to {{1}^{+}}}{\mathop{\lim }}\,\frac{\sqrt{x}-1}{(\sqrt{x}-1)(\sqrt{x}+1)(x-1)({{x}^{2}}-5x+2)}$ $=\underset{x\to {{1}^{+}}}{\mathop{\lim }}\,\frac{1}{(\sqrt{x}+1)(x-1)({{x}^{2}}-5x+2)}=\frac{1}{(2)({{0}^{+}})(-2)}=\frac{1}{{{0}^{-}}}=-\infty $