(+1)+(-2)+(+3)+(-4)+.(+2009)+(-2010)=多少
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/21 17:56:26
![(+1)+(-2)+(+3)+(-4)+.(+2009)+(-2010)=多少](/uploads/image/z/2532499-43-9.jpg?t=%28%2B1%29%2B%28-2%29%2B%28%2B3%29%2B%28-4%29%2B.%28%2B2009%29%2B%28-2010%29%3D%E5%A4%9A%E5%B0%91)
(+1)+(-2)+(+3)+(-4)+.(+2009)+(-2010)=多少
(+1)+(-2)+(+3)+(-4)+.(+2009)+(-2010)=多少
(+1)+(-2)+(+3)+(-4)+.(+2009)+(-2010)=多少
原式=(1-2)+(3-4)+.+(2009-2010)
=﹣1-1-.-1(共1005个﹣1)
=﹣1005