\frac{x^2-1}{x}+\frac{x}{x^2-1}=\frac{5}{2}

crazyshou

\[\$\frac{x^2-1}{x}+\frac{x}{x^2-1}=\frac{5}{2}\$令\$t=\frac{x^2-1}{x}\$，转化为\$t+\frac{1}{t}=2.5\$。\]