so sánh x.y và x+y khi biết 

x=\(1+\sqrt{2}\)

y=\(\sqrt{2}-1\)

so sánh

x=\(\dfrac{1}{\sqrt{2022}-\sqrt{2021}}\)

y=\(\dfrac{1}{\sqrt{2023}-\sqrt{2022}}\)

\(\left(\dfrac{2+\sqrt{x}}{x+2\sqrt{x}+1}-\dfrac{\sqrt{x}-2}{x-1}\right)\cdot\dfrac{x\sqrt{x}+x-\sqrt{x}-1}{\sqrt{x}}\)

\(\dfrac{2+\sqrt{x}}{x+2\sqrt{x}+1}-\dfrac{\sqrt{x}-2}{x-1}\cdot\dfrac{x\sqrt{x}+x-\sqrt{x}-1}{\sqrt{x}}\)

\(\dfrac{1}{\sqrt{3}-\sqrt{2}};\dfrac{1}{\sqrt{4}-\sqrt{3}}\)

so sánh 

\(\left(\dfrac{4\sqrt{x}}{2+\sqrt{x}}+\dfrac{8}{4-x}\right):\left(\dfrac{\sqrt{x}-1}{x-2\sqrt{x}}-\dfrac{2}{\sqrt{x}}\right)\)

\(\left(\sqrt{10}-\sqrt{2}\right)\cdot\sqrt{3+\sqrt{5}}\)

2x² +4x+3=3\(\sqrt{2x^3+3x^2+3x+1}\)