从一个简单的结论出发,从多方面、多角度进行推广,这样做不仅可以得到一些有用的结论,而且对训练学生的思维也是非常有益的;即使有时推广的结论并不十分完美,但是,从训练思维的角度来说,其价值远远大于几个有用的结论.因此,对于学生来说,经常做一些推广的练习是十分必要的.本文试图从一个简单的不等式出发,从几个方面进行推广,希望能抛砖引玉. Starting from a simple conclusion and promoting from many aspects and from multiple perspectives, not only can we get some useful conclusions, but also be very helpful to train our students’ thinking. Even if the conclusions of the promotion are not perfect at times, Training thinking, its value is far greater than a few useful conclusions.Therefore, for students, it is often necessary to do some promotional exercises.This paper attempts to proceed from a simple inequality, from several aspects Promotion, hoping to start a discussion.