解
应该是
(1-1/2²)(1-1/3²)……(1-1/2003²)这个吧
(1-1/2²)=(1-1/2)(1+1/2)=1/2×3/2
(1-1/3²)=(1-1/3)(1+1/3)=2/3×4/3
(1-1/4²)=(1-1/4)(1+1/4)=3/4×5/4
………………………………
原式=(1-1/2)(1+1/2)(1-1/3)(1+1/3)(1-1/4)(1+1/4)+……+(1-1/2003)(1+1/2003)
=1/2×3/2×2/3×4/3×……………………2002/2003×2004/2003
=1/2×2004/2003
=1002/2003