(1+1/2)*(1+1/4)*(1+1/6)*...*(1+1/2008)*(1-1/3)*(1-1/5)*(1-1/7)*...*(1-1/2007)

问题描述:

(1+1/2)*(1+1/4)*(1+1/6)*...*(1+1/2008)*(1-1/3)*(1-1/5)*(1-1/7)*...*(1-1/2007)

(1+1/2)*(1+1/4)*(1+1/6)*...*(1+1/2008)*(1-1/3)*(1-1/5)*(1-1/7)*...*(1-1/2007)
=(1+1/2)*(1-1/3)*(1+1/4)*(1-1/5)*.*(1+1/2006)*(1-1/2007)*(1+1/2008)
=1*1*1*.*1*2009/2008
=2009/2008