简便计算:2009*(1-1/2009)*(1-2008/1)*.*(1-1/2) 需过程清楚,

问题描述:

简便计算:2009*(1-1/2009)*(1-2008/1)*.*(1-1/2) 需过程清楚,

2009*(1-1/2009)*(1-1/2008)*.*(1-1/2)
=2009*2008/2009*2007/2008*……*1/2
=2009*1/2009
=1