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在许多数学题目中,都有一些条件隐含在题意中没有明确给出,这些条件就是所谓的隐含条件.而利用这些隐含条件,可以简捷地解题.下面通过几个例子加以说明.例1下列四式中与(a-3)(1/(3-a))~(1/2)相等的是A.(a-3)~(1/2) B.-(a-3)~(1/2)C.(3-a)~(1/2 D.-(3-a)~(1/2)分析此题的隐含条件是3-a>0,故(a-3)(1/(3-a))~(1/2)=(a-3)((3-a)/(3-a)~2)~(1/2)=(a-3)/(3-a)(3-a)~(1/2)=-(3-a)~(1/2).故选D.例2已知实数a满足|2009-a|+(a-2010)~(1/2)=a,那么a-2009~2的值是_____.分析此题的隐含条件是a-2010≥0,即a≥2010.故|2009-a|+(a-2010)~(1/2)=a可化
In many math problems, there are some conditions implicit in the questions are not clearly given, these conditions are the so-called implicit conditions. And use these implicit conditions, you can simply solve the problem. Here are a few examples to illustrate Example 1 Equal to (a-3) (1 / (3-a)) ~ (1/2) in the following four formulas is A. (a-3) 3) ~ (1/2) C. (3-a) ~ (1/2 D .- (3-a) ~ (1/2) Analysis The implication of this problem is that 3-a> (3-a) to (1/2) = (a-3) (1 / (3-a) (3-a) ~ (1/2) = - (3-a) ~ (1/2). Thus D. Example 2 The known real number a satisfies | 2009-a | + (a-2010) ~ (1/2) = a, then the value of a-2009 ~ 2 is _____. The implication of this problem is that a-2010≥0, that is, a≥2010. | + (a-2010) ~ (1/2) = a can be changed