1*2*3+1-1+1/6=?

1-1/2+1/3-1/4+1/5-1/6+1/7.-1/50=? 巧算：(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)===== 1*2*3+1-1+1/6=? 1-1/2+1/3-1/4+1/5-1/6+…+1/15=23*[1/( )+1/( )+1/( )+1/( )] 1+1/2+18/6/3=? 1+2+3/6+1/4= 1/2+1/3+1/4+1/5+1/6+1/7+.1/20= 已知1/2=1-1/2,1/6=1/2-1/3,1/12=1/3-1/4.计算1/2+1/6+1/12+1/201/30+1/42+1/56+1/72+1/90=? (2/3-1/2+1/6)除以1/24= 2-2x-1/6=x+1/3+1 已知1/2=1-1/2,1/6=1/2-1/3,请计算1/2-1/6-1/12-1/20...-1/132 6/1{4/1[3/1(2/1x-1)+3]+5}=1 解方程 1/6【1/4{1/3（1/2X-1）+3}+5】=1 1/2{1/3[1/4(1/5x-1)-6+3}=1 解方程 1/1*3+1/2*4+1/3*5+1/4*6+.+1/100*102=? 1/2{1/3[1/4(5/1x-1)-6]+3}=1 1/2=1/1-1/2;1/6=1/2-1/3;1/12=1/3-1/4.根据以上规律,计算：1/2+1/6+1/12+20/1+30/1+1/42+1/561/2=1/1-1/2;1/6=1/2-1/3;1/12=1/3-1/4.根据以上规律,计算：1/2+1/6+1/12+1/20+1/30+1/42+1/56 (1-1/2)*(1-1/3)*(1-1/4)*(1-1/5)*(1-1/6)*…*（1-1/19）*（1-1/20）=