(1-1/2012)(1-1/2011)(1-1/2010)...(1-1/3)(1-1/2)=(2011/2012)(2010/2011)(2009/2010)...(2/3)(1/2)=(2011×2010×2009×...×2×1)/(2012×2011×2010×...×3×2)=1/2012顺便说一句,你分子分母写反了,水平书写分...