(1+2/3)*(1-2/3)*(1+2/5)*(1-2/5)*......*(1+2/99)*(1-2/99)=5/3*1/3*7/5*3/5*....99/97*95/97*101/99*97/99=1/3*101/99=101/297
101/297
101/297化简然后约分