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问题: 数学

1-1/2-1/4-1/8-1/16-1/32-1/64-1/128-1/258
/1/2009-1/2008/(绝对值)+/1/2008-1/2007/-/1/2009-1/2007/

解答:

1-1/2-1/4-1/8-1/16-1/32-1/64-1/128-1/258
=1/2 -1/4-1/8-1/16-1/32-1/64-1/128-1/258
=1/4-1/8-1/16-1/32-1/64-1/128-1/258
看出规律了吧
=1/258

|1/2009-1/2008|+|1/2008-1/2007|-|1/2009-1/2007|
分母越大,分数值越小
打开绝对值符号,各个部分两项仍然相减,只是分母小的在前
=1/2008 -1/2009 +1/2007-1/2008 -(1/2007 -1/2009 )
=0