Giải thích các bước giải:
a.Ta có:
$M=\dfrac{x^2}{x^2+2x}+\dfrac{2}{x+2}+\dfrac{2}{x}$
$\to M=\dfrac{x^2}{x(x+2)}+\dfrac{2}{x+2}+\dfrac{2}{x}$
$\to M=\dfrac{x}{x+2}+\dfrac{2}{x+2}+\dfrac{2}{x}$
$\to M=\dfrac{x+2}{x+2}+\dfrac{2}x$
$\to M=1+\dfrac{2}x$
b.Khi $x=-\dfrac32$
$\to M=1+\dfrac{2}{-\dfrac32}$
$\to M=-\dfrac13$