[tex]P =( \frac{3\sqrt{a}}{a+\sqrt{ab}+b} - \frac{3a}{(\sqrt{a}-\sqrt{b})(a+\sqrt{ab}+b)}+\frac{1}{\sqrt{a}-\sqrt{b}}):\frac{(a - 1)(\sqrt{a}-\sqrt{b})}{2(a+\sqrt{ab}+b)} = \frac{3\sqrt{a}(\sqrt{a}-\sqrt{b})-3a+a+\sqrt{ab}+b}{(\sqrt{a}-\sqrt{b})(a+\sqrt{ab}+b)}.\frac{(a+\sqrt{ab}+b)}{(a-1)(\sqrt{a}-\sqrt{b})} =\frac{1}{a-1}[/tex]