\(1,B=\dfrac{4\sqrt{x}+2+3\sqrt{x}-6-5\sqrt{x}+7}{\left(\sqrt{x}-2\right)\left(2\sqrt{x}+1\right)}\\ B=\dfrac{2\sqrt{x}+3}{\left(\sqrt{x}-2\right)\left(2\sqrt{x}+1\right)}\\ 2,C=B:A=\dfrac{2\sqrt{x}+3}{\left(\sqrt{x}-2\right)\left(2\sqrt{x}+1\right)}\cdot\dfrac{5\sqrt{x}\left(\sqrt{x}-2\right)}{2\sqrt{x}+3}\\ C=\dfrac{5\sqrt{x}}{2\sqrt{x}+1}\in Z\\ \Leftrightarrow5\sqrt{x}⋮2\sqrt{x}+1\\ \Leftrightarrow10\sqrt{x}⋮2\sqrt{x}+1\\ \Leftrightarrow5\left(2\sqrt{x}+1\right)-5⋮2\sqrt{x}+1\\ \Leftrightarrow2\sqrt{x}+1\inƯ\left(5\right)=\left\{1;5\right\}\left(2\sqrt{x}+1\ge1\right)\\ \Leftrightarrow\sqrt{x}\in\left\{0;2\right\}\\ \Leftrightarrow x=0\left(x\ne4\right)\)
