г) \(\frac{a}{\sqrt{a}+\sqrt{b}} = \frac{a(\sqrt{a}-\sqrt{b})}{(\sqrt{a}+\sqrt{b})(\sqrt{a}-\sqrt{b})} = \frac{a(\sqrt{a}-\sqrt{b})}{a-b}\)
Ответ: \(\frac{a(\sqrt{a}-\sqrt{b})}{a-b}\)