上式=(1^2-(1/2)^2)*(1^2-(1/3)^2*(1^2-(1/100)^2
=(1*2*3*4*.99)*(3*4*5.101)/((1*2*3.*100)*(1*2*3.*100)
约分后=101/(2*100)=101/200
101/200
上式=(1^2-(1/2)^2)*(1^2-(1/3)^2*(1^2-(1/100)^2
=(1*2*3*4*.99)*(3*4*5.101)/((1*2*3.*100)*(1*2*3.*100)
约分后=101/(2*100)=101/200
101/200