a \(P=\dfrac{1}{2}\cdot\dfrac{9x-1-6x+3\sqrt{x}+\sqrt{x}+1}{9x-1}:\dfrac{9\sqrt{x}+6-9\sqrt{x}-3}{3\sqrt{x}+1}\)
\(=\dfrac{1}{2}\cdot\dfrac{3x+4\sqrt{x}}{9x-1}\cdot\dfrac{3\sqrt{x}+1}{3}\)
\(=\dfrac{3x+4\sqrt{x}}{6\left(3\sqrt{x}-1\right)}\)
b: Để P=6/5 thì \(\dfrac{3x+4\sqrt{x}}{18\sqrt{x}-6}=\dfrac{6}{5}\)
\(\Leftrightarrow15x+20\sqrt{x}-108\sqrt{x}+36=0\)
\(\Leftrightarrow15x-88\sqrt{x}+36=0\)
hay \(x\in\left\{\left(\dfrac{44+2\sqrt{349}}{15}\right)^2;\left(\dfrac{44-2\sqrt{349}}{15}\right)^2\right\}\)
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