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    精英家教网 > 初中数学 > 题目详情
    Given two non-zero real numbers a and b，satisfy |2a-4|+|b+2|+
    		(a-3)b2
    +4=2a    ，then the value of a+b is（　　）
    A、-1B、0C、1D、2
    分析：本题根据非负数、算术平方根的概念和性质，化简解答．
    解答：解：依题意
    .
    2a-4
      
    .
    +
    .
    b+2
      
    .
    +
    		(a-3)b2
    =2a-4，
    ∴2a-4≥0，2a-4+
    .
    b+2
      
    .
    +
    		(a-3)b2
    =2a-4，
    ∴
    .
    b+2
      
    .
    +
    		(a-3)b2
    =0，
    ∴b=-2 a=3，
    ∴a+b=1．
    故选C．
    点评：本题主要考查了非负数、算术平方根的概念及性质，通过变形化简解答．正确理解非负数、算术平方根等概念和性质是解答问题的关键．
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