1-2+3-4+5-6+.+1991-1992+1993
(1-2)+(3-4)+(5-6)+.+1(991-1992)+1993
=(-1)*996+1993
=997
1-2+3-4+5-6+.+1991-1992+1993=?多少呢
3个回答
相关问题
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1-2+3-4+5-6+…+1991-1992+1993=______．
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1-2+3-4+5-6+…+1991-1992+1993=______．
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1-2+3-4+5-6.+1991-1992+1993=?
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1-2+3-4+5-6+…+1991-1992+1993=______．
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1-2+3-4+5-6+…+1991-1992+1993=______．
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帮帮忙1-2+3-4+5-6.1991-1992+1993=?
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(1996+1994+1992+……+6+4+2)-（1+3+5+……+1991+1993+1995）等于多少?
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1998+1997+1996-1995-1994-1993+1992+1991+1990-.+6+5+4-3-2-1=
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计算1998+1997-1996-1995+1994+1993-1992-1991+……+6+5-4-3+2+1
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1993×1993+1992×1992-1993×1992-1992×1991=______．