a: ĐKXĐ: \(x\notin\left\{0;2;-2;3\right\}\)
Ta có: \(P=\left(\dfrac{2+x}{2-x}+\dfrac{4x^2}{x^2-4}-\dfrac{2-x}{2+x}\right):\dfrac{x^2-3x}{2x+x^2}\)
\(=\left(\dfrac{-\left(x+2\right)^2+4x^2-\left(2-x\right)^2}{\left(x+2\right)\left(x-2\right)}\right):\dfrac{x\left(x-3\right)}{x\left(x+2\right)}\)
\(=\dfrac{-x^2-4x-4+4x^2-x^2+4x-4}{\left(x+2\right)\left(x-2\right)}\cdot\dfrac{x+2}{x-3}\)
\(=\dfrac{2x^2-8}{x-2}\cdot\dfrac{1}{x-3}\)
\(=\dfrac{2\left(x-2\right)\left(x+2\right)}{x-2}\cdot\dfrac{1}{x-3}\)
\(=\dfrac{2x+4}{x-3}\)
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