Explicație pas cu pas:
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[tex]\it \dfrac{x^2-4}{x^2-x-2}=\dfrac{x^2-2^2}{x-2x+x-2}=\dfrac{(x-2)(x+2)}{x(x-2)+(x-2)}=\\ \\ \\ =\dfrac{(x-2)(x+2)}{(x-2)(x+1)}=\dfrac{x+2}{x+1}[/tex]
