运算作为一种必须的数学技能,会运算、正确运算、简约运算是对运算能力的3个不同层次的要求,其中正确运算是“必须”.运算能力考量着学生的诸如数感、符号感、观察、决策、逻辑思维等多种能力.尽管电子辅助计算工具能够又快又对地给出结果,但计算工具无法取代这些能力的培养与提高.数与式教学的一个重要任务是运算能力的培养与提高.与整式相比,分式的分母中含有字母,因而比整式运算更容易出错.那么如 Computation as a necessary mathematical skills, computing, correct computing, simple computing is the computing power of the three different levels of requirements, of which the correct operation is “must ” computing capacity of students such as number sense, symbols Sense, observation, decision-making, logical thinking, etc. Although electronic aided computing tools can give results quickly and accurately, computing tools can not replace the cultivation and improvement of these abilities.One of the important tasks of counting and teaching is computing Ability to cultivate and improve. Compared with the integral, the fractional denominator contains letters, and therefore more error-prone than the integer operation.