挖掘隐含条件解二次根式问题

• 作 者: 刘永生
• 机 构: 江西省赣县二中,
• 出 处: 数学大世界(初中版)
• 发表日期: 2013年11期
• 关键词: 隐含条件 二次根式 解决问题 题目 特质 解题

一般地,形如a~(1/2)(a≥0)的式子叫做二次根式.从定义可知:二次根式有a≥0和a~(1/2)(a≥0)≥0的两个非负特质,这两个特点隐含在题目中,所以解题时应先将其挖掘出来,才能正确顺利地解决问题,现举例加以说明.例1请判断小明对下式的化简是否正确.(?)分析从题中可知隐含的条件是-4x~3≥0且-x>0,所以x<0,由a~(1/2)(a≥0)的非负性知小明的化简是不

In general, the form of a ~ (1/2) (a ≥ 0) is called the quadratic root. From the definition we can see: the quadratic root has a ≥ 0 and a ~ (1/2) (a ≥ 0) ≥ 0 two non-negative traits, these two characteristics are implicit in the title, so the problem should be first excavated in order to correctly and smoothly solve the problem, are examples to illustrate .Example 1 Please determine the next type (?) Analysis from the title we can see that the implied conditions are -4x ~ 3≥0 and -x> 0, so x <0, by a ~ (1/2) (a ≥ 0) Minimize the negative knowledge that the reduction is not