在数学教学中,数和形是两个最重要的研究对象.对于一类代数问题,若能转化为图形性质的问题,往往会使复杂问题简单化,抽象问题具体化,从而获得简洁的解决方案.一、整式乘法法则的探究例1探究乘法法则:(a+b)(c+d)=ac+ad+bc+bd.解如图1,构造长、宽为(a+b)和(c+d)的矩形,再将其分割为四个小矩形,通过“总体——分割”的两种方法计算矩形的面 In maths teaching, the number and shape are the two most important research objects.For a class of algebraic problems, if they can be transformed into the graphic nature, they often simplify complicated problems and abstract problems, so as to obtain concise solutions (A + b) (c + d) = ac + ad + bc + bd. Solution As shown in Figure 1, the structure is long and the width is (a + b) and (c + d) of the rectangle, and then divided into four small rectangles, through the “total - division” of the two methods to calculate the rectangular surface