x-2x+3x-4x+5x+.+2007x-2008x

分类: 作业答案 • 2021-12-20 01:28:29

问题描述：

答

x-2x+3x-4x+5x+........+2007x-2008x
=x(1-2+3-4+5`````+2007-2008)
=x[(1-2)+(3-4+(5-6)+``````(2007-2008)]
=x(-1*1004)
=-1004x

答

x-2x+3x-4x+5x+........+2007x-2008x
=x(1-2+3-4+5`````+2007-2008)
=x[(1-2)+(3-4+(5-6)+``````(2007-2008)]
=x(-1*1004)
=-1004x

答

-1004x