题目:若正数a、b满足ab=a+b+3,求ab的取值范围.(1999年全国高考题)这是一道有关函数与不等式的形式简单、结构优美的小综合题.从代数与几何的视角观察和分析题目的条件与结论,我们将产生多种不同的念头,可以获得基本不等式解法、数列解法、三角解法、方程解法等多种解法.由于各种解法均涉及高中代数主干知识,同时蕴藏着丰富的数学思想方法,因此本题 Title: If the positive number a, b meet ab = a + b + 3, find the range of ab. (1999 National College Entrance Examination) This is a form of simple functions, simple structure, beautiful structure of the small comprehensive questions. Algebraic and geometric perspectives to observe and analyze the conditions and conclusions of the topic, we will have a variety of different ideas, you can get the basic inequality solution, the number of solutions, the triangle solution, equation solutions and other solutions.Because the various solutions involve high school algebra The main knowledge, at the same time, contains a wealth of mathematical thinking, so this question