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Решите задачу:

$\cfrac{\sqrt[3]{x}+\sqrt[3]{y}}{x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}}}-\cfrac{\sqrt[3]{x}-\sqrt[3]{y}}{\sqrt[3]{x^2}-\sqrt[3]{y^2}}=\cfrac{\sqrt[3]{x}+\sqrt[3]{y}}{x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}}}-\cfrac{1}{\sqrt[3]{x}+\sqrt[3]{y}}=\\\\\\\cfrac{(\sqrt[3]{x}+\sqrt[3]{y})^2}{(\sqrt[3]{x}+\sqrt[3]{y})(x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}})}-\cfrac{x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}}}{(\sqrt[3]{x}+\sqrt[3]{y})(x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}})}=\\\\\\$ $\cfrac{(\sqrt[3]{x})^2+2\sqrt[3]{x}\sqrt[3]{y}+(\sqrt[3]{y})^2-(x^{\frac{2}{3}}-\sqrt[3]{xy}+y^{\frac{2}{3}})}{(\sqrt[3]{x})^3+(\sqrt[3]{y})^3}=\\\\\\\cfrac{(\sqrt[3]{x})^2+2\sqrt[3]{xy}+(\sqrt[3]{y})^2-x^{\frac{2}{3}}+\sqrt[3]{xy}-y^{\frac{2}{3}}}{x+y}=\cfrac{3\sqrt[3]{xy}}{x+y}$