Question

MN giúp mK rút gọn con này nha:

\(A=\frac{\sqrt{X}+1}{\sqrt{X}-2}+\frac{2\sqrt{2}}{\sqrt{X}+2}+\frac{2+5\sqrt{X}}{4-X}\)

Answer 1

\(A=\frac{\left(\sqrt{x}+1\right)\left(\sqrt{x}+2\right)+2\sqrt{2}\left(\sqrt{x}-2\right)-2-5\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}=\frac{x+3\sqrt{x}+2+2\sqrt{2}.\sqrt{x}-4\sqrt{2}-2-5\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\)

\(=\frac{x+2\sqrt{x}\left(\sqrt{2}-1\right)-4\sqrt{2}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}=\frac{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\sqrt{2}\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}=\frac{\sqrt{x}+2\sqrt{2}}{\sqrt{x}+2}\)