Cho biểu thức:
\(M=\left(\frac{\sqrt{x}+1}{\sqrt{2x}+1}+\frac{\sqrt{2x}+\sqrt{x}}{\sqrt{2x}-1}-1\right)\)\(:\left(1+\frac{\sqrt{x}+1}{\sqrt{2x}+1}-\frac{\sqrt{2x}+\sqrt{x}}{\sqrt{2x}-1}\right)\)
a/ Rút gọn M
b/ Tính M khi \(x=\frac{1}{2}\left(3+2\sqrt{2}\right)\)