Question

Rút gọn: \(\left(\dfrac{x-2\sqrt{3x}+3}{x-3}\right)\left(\sqrt{4x}+\sqrt{12}\right)\)

Answer 1

\(=\dfrac{\left(\sqrt{x}-\sqrt{3}\right)^2}{\left(\sqrt{x}-\sqrt{3}\right).\left(\sqrt{x}+\sqrt{3}\right)}.\left(2\sqrt{x}+\sqrt{12}\right)\)

\(=\dfrac{\sqrt{x}-\sqrt{3}}{\sqrt{x}+\sqrt{3}}.2\left(\sqrt{x}+\sqrt{3}\right)\)

\(=2.\left(\sqrt{x}-\sqrt{3}\right)\)

 

Answer 2

Với `x ne 3;x >= 0` có:

`[(\sqrt{x}-3)^2]/[(\sqrt{x}-3)(\sqrt{x}+3)].(2\sqrt{x}+2\sqrt{3})`

`=[\sqrt{x}-3]/[\sqrt{x}+3].2(\sqrt{x}+3)`

`=2(\sqrt{x}-3)`

`=2\sqrt{3}-6`