计算 (-1)+(+2)+(-3)+(+4)+(-5)+.+(-2009)+(+2010)
计算 (-1)+(+2)+(-3)+(+4)+(-5)+.+(-2009)+(+2010)
=(2-1)+(4-3)+(6-5)+……+(2010-2009)
=1+1+1+……+1
=1×1005
=1005
(-1+2)+(-3+4)+(-5+6)-......+(-2009+2010)
= 1 + 1 + 1 + ......+ 1 =2010/2=1005
(-1)+(+2)+(-3)+(+4)+(-5)+.+(+2008)+(-2009)+(+2010)计算
原式=-(1+2009)*2010/2/2+(2+2010)*2010/2/2
=1005/2*2
=1005
或
原式=1005*1=1005
计算:1-2+3-4+5-6+.+2009-2010
原式=(1-2)+(3-4)+…+(2009-2010)
=-1-1-1-…-1
=-1*(2010/2)
=-1005
(-1)-2-3-4-.-1000 1-2+3-4+5-6+.+2009-2010计算
-1-2-3-4-...-1000
=-(1+2+3+4+...+1000)
=-(1+1000)x(1000/2)
=-1001x500
=-500500
1-2+3-4+5-6+...+2009-2010
=(1-2)+(3-4)+(5-6)+...+(2009-2010)
=(-1)x(2010/2)
=(-1)x1005
=-1005
因为|a+b|=-(a-b),且a不等于b
所以a+b<0
因为|a|=10,|b|=15
所以1、a=10,b=-15
2、a=-10,b=-15
所以1、a-b=10-(-15)=25
2、a-b=-10-(-15)=5
计算2013-2012+2010-2009+.+5-4+3-2+1
2013-2012+2010-2009+...+5-4+3-2+1
=【2013-2012】+【2010-2009】+...+【5-4】+【3-2】+【1-0】
=2014÷2
=1007
5.计算:(-1)+(+2)+(-3)+(+4)+…+(-99)+(+100)+…+(-2009)+(+2010)=()
(-1)+(+2)+(-3)+(+4)+…+(-99)+(+100)+…+(-2009)+(+2010)
=【(-1)+(+2)】+【(-3)+(+4)】+…+【(-99)+(+100)】+…+【(-2009)+(+2010)】
=1+1+……+1+1
=1005
计算(1+3+5。+2009)-(2+4+6+2010)
(1+3+5.。。。+2009)-(2+4+6+2010)
=(1-2)+(3-4)+(5-6)+....+(2009-2010)
=-1-1-1-.........-1
=-1*2010/2
=1005
计算:(1+3+5+.+2009)-(2+4+6+.+2010)=?
=(1-2)+(3-4)+(5-6)+.......+(2009-2010)
=-1*1005=-1005