快
问题描述：
快
(1+1/2)乘（1-1/2)乘(1+1/3)乘(1-1/3)乘.乘(1+1/99)乘(1-1/99)
(1-1/2乘1/2)乘(1-1/3乘1/3)乘(1-1/4乘1/4)乘.乘(1-1/2005乘1/2005)
4.75乘1.36除以4.75除以0.68除以0.375乘0.75
答
(1+1/2)乘（1-1/2)乘(1+1/3)乘(1-1/3)乘.乘(1+1/99)乘(1-1/99) =3/2*4/3*5/4*...*100/99*1/2*2/3*3/4*...*98/99=100/2*1/99=50/99(1-1/2乘1/2)乘(1-1/3乘1/3)乘(1-1/4乘1/4)乘.乘(1-1/2005乘1/2005) =(1+1/2)(1-1/2)...