论文部分内容阅读
学习了一元一次不等式组的解法之后,我们就会经常遇到求一元一次不等式组中字母系数的值或求其取值范围的问题.不少学生对解决这样的问题感到十分困难.事实上,只要能灵活运用不等式组解集的知识即可顺利求解.下面根据所给条件的不同,分四种解集情况举例说明.1.应用“同大取大”确定字母系数的取值例1不等式组x>a x{>3的解集是x>3,求a的取值范围.分析:不等式组的解集是不等式组中两个不等式解集的公共部分.首先由口诀“同大取大”得知,两个不等式中一
After learning the solution of a unitary inequality group, we often encounter the problem of finding the value of the letter coefficient in the unitary inequality group or the range of its value.Many students find it very difficult to solve such a problem.In fact, As long as the flexibility to use the inequality set solution knowledge can be successfully solved.According to the different conditions given below, an example of four kinds of solution sets are given as examples.1.Application of “big with big” to determine the value of the letter example 1 inequality group x> ax {> 3 solution set is x> 3, find the range of values.Analysis: inequality group solution set is inequality group of two inequality sets of public part of the first by the formula Big big "that, one of the two inequalities