(1/2009-1)(1/2008-1)(1/2007-1)……(1/3)(2/1)计算

问题描述:

(1/2009-1)(1/2008-1)(1/2007-1)……(1/3)(2/1)计算

(1/2009-1)(1/2008-1)(1/2007-1)……(1/3-1)(2/1-1)
=(-2008/2009)×(-2007/2008)×(-2006/2007)×……×(-2/3)×(-1/2)
=2008/2009×2007/2008×2006/2007×……×2/3×1/2
=1/2009