化简:X-2X+3X-4X+5X-……+2001x-2002x
问题描述:
化简:X-2X+3X-4X+5X-……+2001x-2002x
答
X-2X+3X-4X+5X-……+2001x-2002x
=X(1-2+3-4+5-……+2001-2002)
=X(-1-1-.-1)
=X(-1)*1001
=-1001X