“数”和“形”是相互联系的,数轴和直角坐标系的建立,为“数”和“形”的沟通提供了工具.本文举一例谈借助数轴求数的问题,让同学们学习品赏,例有一列数,第1个数是105,第2个数是85,从第3个数开始,每个数都是它前面两个数的平均数.那么,第19个数的整数部分是多少? 分析如果直接求第19个数,则不堪 “Number” and “shape” are interrelated, and the establishment of numerical and rectangular coordinate systems provides tools for the communication of “numbers” and “shapes.” This paper gives an example of the problems of counting numbers through the use of axes to allow students to learn Rewards, there is a list of cases, the first number is 105, the second number is 85, starting from the third number, each number is the average of the first two numbers. Then, the 19th number of integers How much is the part? If the analysis directly seeks the 19th number, it is unbearable.