式子(1/2)a表示非负数a的算术平方根,它是一个非负数,而a是被开方数,它也是一个非负数,这就是二次根式的双重非负性.这种双重非负性在数学中占有极其重要的位置,所以在解题中一定要注意这两个隐含条件.现列举这一性质在几类试题中的运用,以供大家参考.一、确定自变量的取值范围例1若下列式子有意义,试确定x的取 The formula (1/2) a represents the arithmetic square root of the nonnegative number a, which is a nonnegative number, and a is the square root of the number, which is also a nonnegative number, which is a quadratic double nonnegative. Non-negative occupies an extremely important position in mathematics, so in the problem-solving must pay attention to these two implied conditions .Considering the nature of the use of several types of questions for your reference .A determine the independent variables The range of values ​​Example 1 If the following formula makes sense, try to determine the x take