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For each pair of real numbers a≠b,define the operation★as (a★b)=数学公式,then the
value of ((1★2)★3) is
(英汉小词典:each pair每对;real numbers实数;define定义;operation运算;value值)


  1. A.
    数学公式
  2. B.
    数学公式
  3. C.
    0
  4. D.
    数学公式
C
分析:按题中所给的新定义的运算,代入数据即可得解.
解答:∵(a★b)=
∴((1★2)★3)
=(()★3)
=((-3)★3)
=
=0
点评:此题主要考查对新定义的理解运用能力,也是常见题型.
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