(1+1/2+1/3+1/4)*(1/2+1/3+1/4)-(1/2+1/3+1/4+1/5)*(1/2+1/3+1/4)简算过程

问题描述:

(1+1/2+1/3+1/4)*(1/2+1/3+1/4)-(1/2+1/3+1/4+1/5)*(1/2+1/3+1/4)简算过程
不要有字母的那种解法

原公式=(1/2+1/3+1/4)+(1/2+1/3+1/4)*(1/2+1/3+1/4)-(1/2+1/3+1/4)*(1/2+1/3+1/4) - (1/5)*(1/2+1/3+1/4)=(1/2+1/3+1/4) - (1/5)*(1/2+1/3+1/4)= (1-1/5)*(1/2+1/3+1/4)=(4/5)*(1/2+1/3+1/4)=2/5+4/15+1/5=3/5+4/15...