\(\frac{4}{x+2}+\frac{2}{x-2}+\frac{5x-6}{4-x^2}\)
\(=\frac{4\left(x-2\right)+2\left(x+2\right)-\left(5x-6\right)}{x^2-4}\)
\(=\frac{4x-8+2x+4-5x+6}{x^2-4}\)
\(=\frac{x+2}{\left(x-2\right)\left(x+2\right)}=\frac{1}{x-2}\)
điều kiện x khác {2,-2}
\(\frac{4}{x+2}+\frac{2}{x-2}+\frac{5x-6}{4-x^2}=\frac{4x-8+2x+4-5x+6}{x^2-4}\)
=\(\frac{x+2}{\left(x+2\right)\left(x-2\right)}=\frac{1}{x-2}\)
\(\frac{4}{x+2}+\frac{2}{x-2}+\frac{5x-6}{4-x^2}\)
\(=\frac{4}{x+2}+\frac{2}{x-2}+\frac{6-5x}{x^2-4}\)
\(=\frac{4\left(x-2\right)+2\left(x+2\right)+6-5x}{\left(x-2\right)\left(x+2\right)}\)
\(=\frac{4x-8+2x+4+6-5x}{\left(x-2\right)\left(x+2\right)}\)
\(=\frac{x+2}{\left(x-2\right)\left(x+2\right)}\)
\(=\frac{1}{x-2}\)
