\(\dfrac{x}{x+4}+\dfrac{4}{x-4}-\dfrac{32}{x^2-16}\)
\(=\dfrac{x\left(x-4\right)+4\left(x+4\right)-32}{\left(x+4\right).\left(x-4\right)}\)
\(=\dfrac{x^2-4x+4x+16-32}{\left(x+4\right).\left(x-4\right)}\)
\(=\dfrac{x^2-16}{x^2-16}\)
\(=1\)
Ta có: \(\dfrac{x}{x+4}+\dfrac{4}{x-4}-\dfrac{32}{x^2-16}\)
\(=\dfrac{x\left(x-4\right)}{\left(x+4\right)\left(x-4\right)}+\dfrac{4\left(x+4\right)}{\left(x-4\right)\left(x+4\right)}-\dfrac{32}{x^2-16}\)
\(=\dfrac{x^2-4x+4x+16-32}{\left(x-4\right)\left(x+4\right)}\)
\(=\dfrac{x^2-16}{\left(x-4\right)\left(x+4\right)}\)
\(=\dfrac{\left(x-4\right)\left(x+4\right)}{\left(x-4\right)\left(x+4\right)}=1\)
