教学中,经常会遇到一些含有参数的极值问题,这类问题的知识综合性比较强,思维的灵活性比较高.因之,学生解答起来就不怎么顺利.比如87年上海市高考数学试题第六题(2)“在 xoy 平面上给定曲线 y~2=2x,设点 A 的坐标为(a,0),a∈R,求曲线上点到点 A 的距离之最小值 d,并写出 d=f(a)的函数表达式。”我布置给学生去做,结果是在 In teaching, you often encounter extreme problems with parameters. The knowledge of such problems is more comprehensive and the flexibility of thinking is higher. Therefore, the students do not get a smooth answer. For example, in 87 years of mathematics in Shanghai college entrance examination Question 6 (2) “Set the curve y~2=2x on the xoy plane. Set the coordinates of the point A to (a, 0), a∈R. Find the minimum distance from the point on the curve to point A. , and write a function expression for d=f(a).” I arranged for the students to do it. The result was