在分式运算中,要经常进行通分,而有些分式运算,用一次通分的方法往往运算比较繁,若能根据分式的结构特点,灵活运用技巧,则可收到事半功倍的效果.一、约分后通分例1计算(x2+2xy+y2)/(x2y+xy2)-(x2-2xy+y2)/(x2y-xy2) 分析分式的分子与分母有公因式,故先约分,然后通分. In the fractional operation, it is necessary to carry out the pass-through frequently. However, some fractional operations often operate more frequently with one-pass methods. If you can flexibly use the skills according to the structural features of fractional systems, you can receive more effective results. First, about points after the pass Example 1 Calculation (x2 +2 xy + y2) / (x2y + xy2) - (x2-2xy + y2) / (x2y-xy2) Analytical fractional numerator and denominator have a common factor First about points, and then points.