解：1/(X-1)+1/(X-2)=2/XX(X-2)+X(X-1)=(X-1)(X-2) ...... 去滑凳分母，方信敬旅程两边同时乘以X(X-1)(X-2)X平方-2X+X平方-X=X平稿者方-3X+2X平方=2X=正负根下2
