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1.计算1-2+3-4+5-6+······-2010+2011最后等于 2.2008又5/6+(-2009又3/4)-

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1.计算1-2+3-4+5-6+······-2010+2011最后等于 2.2008又5/6+(-2009又3/4)-2010又1/2+2011又2/3
好的加分!!!!!+++++5
1-2+3-4+5-6+······-2010+2011
=-1-1-1-...-1+2011
=-1*1005+2011
=2011-1005
=1006
2008+5/6+(-2009-3/4)-2010-1/2+2011+2/3
=2008+5/6-2009-3/4-2010-1/2+2011+2/3
=2008-2009-2010+2011+5/6-3/4-1/2+2/3
=-1+1+5/6-3/4-1/2+2/3
=5/6+2/3-3/4-1/2
=5/6+4/6-3/4-1/2
=9/6-3/4-1/2
=3/2-3/4-1/2
=1-3/4+1/2-1/2
=1-3/4
=1/4