著名数学家华罗庚说过:“数无形时少直观,形少数时难入微。”求极值是一类常见的问题,也是一类题型多变难度较大的问题,但若从条件和问题的特点出发,采取数形结合,往往会使复杂的问题简单化、直观化、明朗化,会收到事半功倍的效果。 Hua Luogeng, a famous mathematician, said: “When the number of intangibles is less and less intuitive, it is very difficult to form a few.” Extremum is a common type of problem, but also a type of question is more difficult and more difficult, but if from the conditions And the characteristics of the problem starting to take a combination of several forms, often complicated problems will be simplified, intuitive, clear, will receive a multiplier effect.