Question

Rút gọn biểu thức \(M=\left(\sqrt{x}-\dfrac{3\sqrt{x}-1}{1+\sqrt{x}}\right)\left(\dfrac{\sqrt{x}}{x+\sqrt{x}+1}-\dfrac{2x+1}{x\sqrt{x}-1}\right)\) với \(x\ge0;x\ne1\)

Answer 1

\(M=\left(\dfrac{\sqrt{x}\left(\sqrt{x}+1\right)}{\sqrt{x}+1}-\dfrac{3\sqrt{x}-1}{\sqrt{x}+1}\right)\left(\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x^3}-1}-\dfrac{2x+1}{\sqrt{x^3}-1}\right)\)

\(M=\left(\dfrac{x+\sqrt{x}-3\sqrt{x}+1}{\sqrt{x}+1}\right)\left(\dfrac{x-\sqrt{x}-2x-1}{\sqrt{x^3}-1}\right)\)

\(M=\left(\dfrac{x-2\sqrt{x}+1}{\sqrt{x}+1}\right)\left(\dfrac{-x-\sqrt{x}-1}{\sqrt{x^3}-1}\right)\)

\(M=\dfrac{\left(\sqrt{x}-1\right)^2}{\sqrt{x}+1}\dfrac{-\left(x+\sqrt{x}+1\right)}{\left(\sqrt{x}-1\right)\left(x+\sqrt{x}+1\right)}\)

\(M=\dfrac{1-\sqrt{x}}{\sqrt{x}+1}\)