(1/2008-1)×(1/2007-1)×(1/2006-1)×……×(1/3-1)×(1/2-1)

问题描述:

(1/2008-1)×(1/2007-1)×(1/2006-1)×……×(1/3-1)×(1/2-1)

(1/2008-1)×(1/2007-1)×(1/2006-1)×……×(1/3-1)×(1/2-1)
=-2007/2008×2006/2007×2005/2006×……×2/3×1/2
=-1/2008