七年级数学1/3-1/2的绝对值加1/4-1/3的绝对值加1/5-1/4的绝对值加。。。。。。1/2007-1/2006的绝对值
∵|1/3-1/2|=-(1/3-1/2)=-1/3+1/2
|1/4-1/3|=-(1/4-1/3)=-1/4+1/3
|1/5-1/4|=-(1/5-1/4)=-1/5+1/4
……
|1/2006-1/2005|=-(1/2006-1/2005)=-1/2006+1/2005
|1/2007-1/2006|=-(1/2007-1/2006)=-1/2007+1/2006
∴将上述式子依次相加,即:
-1/3+1/2-1/4+1/3-1/5+1/4……-1/2006+1/2005-1/2007+1/2006
=1/2-1/2007
=2005/4014
。 全部
∵|1/3-1/2|=-(1/3-1/2)=-1/3+1/2
|1/4-1/3|=-(1/4-1/3)=-1/4+1/3
|1/5-1/4|=-(1/5-1/4)=-1/5+1/4
……
|1/2006-1/2005|=-(1/2006-1/2005)=-1/2006+1/2005
|1/2007-1/2006|=-(1/2007-1/2006)=-1/2007+1/2006
∴将上述式子依次相加,即:
-1/3+1/2-1/4+1/3-1/5+1/4……-1/2006+1/2005-1/2007+1/2006
=1/2-1/2007
=2005/4014
。
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