Question

giúp mình câu cuối này đc không?

Answer 1

\(a,\Rightarrow A=\dfrac{\sqrt{x}+1+\sqrt{x}-1}{\left(\sqrt{x}-1\right)\left(\sqrt{x}-1\right)}.\dfrac{\left(\sqrt{x}-1\right)\left(\sqrt{x}-1\right)}{2}\)

\(\Rightarrow A=\dfrac{2\sqrt{x}\left(\sqrt{x}-1\right)\left(\sqrt{x}-1\right)}{2\left(\sqrt{x}-1\right)\left(\sqrt{x}-1\right)}\)

\(\Rightarrow A=\sqrt{x}\)

b, \(A=3\Rightarrow\sqrt{x}=3\Rightarrow x=9\)