For each pair of real numbers a≠b,define the operation★as (a★b)=數(shù)學(xué)公式,then the
value of ((1★2)★3) is
(英漢小詞典:each pair每對(duì);real numbers實(shí)數(shù);define定義;operation運(yùn)算;value值)


  1. A.
    數(shù)學(xué)公式
  2. B.
    數(shù)學(xué)公式
  3. C.
    0
  4. D.
    數(shù)學(xué)公式
C
分析:按題中所給的新定義的運(yùn)算,代入數(shù)據(jù)即可得解.
解答:∵(a★b)=
∴((1★2)★3)
=(()★3)
=((-3)★3)
=
=0
點(diǎn)評(píng):此題主要考查對(duì)新定義的理解運(yùn)用能力,也是常見題型.
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