Tìm P biết P+(4x-12)/(x^#-3x^2-4x+12)=3/(x-3)-(x^2/4-x^2)

* Hướng dẫn giải

$$\begin{gathered} ĐK: x\ne \left\{-2,2,3\right\} \\ P=\frac{3}{x-3}-\frac{x^2}{4-x^2}-\frac{4x-12}{x^3-3x^2-4x+12} \\ P=\frac{3(x^2-4)}{(x-3)(x^2-4)}+\frac{x^2(x-3)}{(x-3)(x^2-4)}-\frac{4x-12}{(x-3)(x^2-4)} \\ P= \frac{x^3-4x}{(x-3)(x-2)(x+2)} \\ P=\frac{x}{x-3} \\ Đáp án B \end{gathered}$$