Question

Rút gọn \(A=\dfrac{2}{\sqrt{X}-2}:\left(\dfrac{3}{\sqrt{X}-2}-\dfrac{\sqrt{X}+4}{X-4}\right)\)

 

Answer 1

\(=\dfrac{2}{\sqrt{x}-2}:\dfrac{3\sqrt{x}+6-\sqrt{x}-4}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\)

=2

Answer 2

\(A=\dfrac{2}{\sqrt{x}-2}:\dfrac{3\sqrt{x}+6-\sqrt{x}-4}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\left(x\ge0;x\ne4\right)\\ A=\dfrac{2}{\sqrt{x}-2}\cdot\dfrac{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}{2\left(\sqrt{x}+1\right)}=\dfrac{\sqrt{x}+2}{\sqrt{x}+1}\)