1997+1996-1995-1994+1993+1992```-2+1

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 00:38:18
1997+1996-1995-1994+1993+1992```-2+1

1997+1996-1995-1994+1993+1992```-2+1
1997+1996-1995-1994+1993+1992```-2+1

1997+1996-1995-1994+1993+1992```-2+1
一共1997个数,1997--2这1996个每4个一组
每组4个数的代数和为:1997+1996-1995-1994=4
一共有1996÷4=499组
1997+1996-1995-1994+1993+1992```-2+1
=(1997+1996-1995-1994)×(1996÷4)+1
=4×499+1
=1997

=(1997+1996-1995-1994)+(1993+1992-1991-1990)+..```(5+4-3-2)+1
=4*(1997-1)/4+1
=1997

4

1997+1996-1995-1994+1993+1992```-2+1
=(1997+1996-1995-1994)+(1993+1992-1991-1990)```+(5+4-3-2)+1
=4*(1997-1)/4+1
=1997

1997