5. $$rac{a^2+b^2}{2a-b} + (2a+b) =$$

$$\frac{a^2+b^2}{2a-b} + (2a+b) = \frac{a^2+b^2 + (2a+b)(2a-b)}{2a-b} = \frac{a^2+b^2 + 4a^2 - b^2}{2a-b} = \frac{5a^2}{2a-b}$$ $$\textbf{Ответ: } \frac{5a^2}{2a-b}$$