问题
填空题
1-2+3-4+5-6+…+2001-2002的值是______.
答案
1-2+3-4+5-6+…+2001-2002
=(1-2)+(3-4)+(5-6)+…+(2001-2002)
=-1×1001
=-1001.
故应填-1001.
1-2+3-4+5-6+…+2001-2002的值是______.
1-2+3-4+5-6+…+2001-2002
=(1-2)+(3-4)+(5-6)+…+(2001-2002)
=-1×1001
=-1001.
故应填-1001.