培养学生具有正确、迅速的运算能力,是中专数学教学的重要目的之一。运算的合理化技巧是正确、迅速运算的保证。培养学生运算的合理化技巧,不仅可以锻炼学生的观察、分析能力,使思维敏捷而深刻,而且会使学生在将来的学习和工作中善于独立思考,富有创造精神。一、统览全局整体分析每个题目都是一个整体,解题中要有全局观点,每步运算都要眼观全局,具有明确的目的,对于中间结果有时则不必求出。例1 已知等差数列{a_n}的前10项之和为 Cultivating students with the correct and rapid computing skills is one of the important goals of secondary mathematics teaching. The rationalization of operations is a guarantee of correct and rapid operations. Cultivating the rationalization skills of students’ calculations can not only train students’ observation and analysis abilities, but also enable them to have agile and profound thinking, and it will enable students to be good at independent thinking and creative spirit in their future studies and work. First, the overall overview of the overall analysis of each topic is a whole, the problem should have a global perspective, each step should be eyed the overall situation, with a clear purpose, sometimes do not have to find the intermediate results. Example 1 The sum of the first 10 items of the known arithmetic difference sequence {a_n} is