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[求助] SOS.....数学盲求助数学题

SOS.....数学盲求助数学题

计算:  111...1×   999...9
             ┖2002个┚ ┖2002个┚.

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SOS~.

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111......1×  999.,,,..9
┖2002个┚   ┖2002个┚
=111.......1× (100........0 - 1)
  ┖2002个┚     ┖2002个┚
=111.......100..........0-111.......1
  ┖2002个┚┖2002个┚  ┖2002个┚
=111........10888.......89
   ┖2001个┚  ┖2001个┚.

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[ 本帖最后由 yangjun6910 于 2008-7-8 21:10 编辑 ].

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简单!!

有两种做法:
Number  1
        1111...111(2002个)x[100...00(2002 个0)-1]
=1111....1111(2002个)x1000...0000(2002 个0)-1111....1111(2002个)
=  111...1111(2002个)00.....0000(2002个)-1111....1111(2002个)
=  111.....11111(2001个1)0888....8888(2001个8)9



Number  2
    找规律:

99x11=1089
999x111=110889
9999x1111=11108889
.......
.........
...........
9999...9999(2002个)x1111....1111(2002个)
= 111.....11111(2001个1)0888....8888(2001个8)9

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太厉害了.

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