a, đk x khác -1 ; 3
\(A=\dfrac{\left(2x-3\right)\left(x^2-2x+1\right)-8x+12}{\left(x^2+2x+1\right)\left(x-3\right)}=\dfrac{2x^3-4x^2+2x-3x^2+6x-3-8x+12}{x^3-3x^2+2x^2-6x+x-3}\)
\(=\dfrac{2x^3-7x^2+9}{x^3-x^2-5x-3}=\dfrac{\left(x+1\right)\left(x-3\right)\left(2x-3\right)}{\left(x-3\right)\left(x+1\right)^2}=\dfrac{2x-3}{x+1}\)
b, \(\dfrac{2x-3}{x+1}>2\Leftrightarrow2x-3>2x+2\)(vô lí)
Vậy ko có giá trị x thỏa mãn
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