现行新编初中代数第四册中一元二次方程的图象解法(选学内容)一节,利用图象求方程x~2-2x-2=0的实数根,教科书上给出两种解法。其中第二种解法比较简便,但当遇到交点的纵坐标的绝对值比较大时,在作图的技术上带来一定的困难,怎样解决这些问题呢?我在教学中作了如下处理。在介绍了第二种解法后,向学生指出,利用二次函数的图象解一元二次方程的方法是很多的,要灵活运用。如将原方程 The image solution method of the quadratic equation in the fourth edition of the current new junior high school algebra (selection content), uses the real root of the equation x~2-2x-2=0 in the image, and two solutions are given in the textbook. . The second solution is relatively simple, but when the absolute value of the ordinate that encounters the intersection point is relatively large, the drawing technique brings certain difficulties. How to solve these problems? I did the following in teaching. After introducing the second solution, I pointed out to students that there are many ways to solve quadratic equations using images of quadratic functions, and we must use them flexibly. As the original equation