(3-2/1)/(4/1+2) 9-(12/1+8/1)*24\ (2-2*3/2)/9/2 9/4*15+9/5/15/1 (简便运算)

1:8 2:9 1:9 3:4 1:3 ... |1-1/2|-|1/2-1/3|-|1/3-1/4|-.-|1/9-1/10| |1-1/2|+|1/2-1/3|+|1/3-1/4|+...|1/9-1/10| 1*2/1+2*3/1+3*4/1+...+8*9/1+9*10/1简算 /1/3-1/2/+/1/4-1/3/+/1/5-1/4/+.+/1/10-1/9/ |1/3-1/2|+|1/4-1/3|+|1/5-1/4|+...+|1/10-1/9| 有理数:-1/2+1/3-(-1/9)-1/4= 1/1*3+1/2*4+...+1/9*11=? (1-1/2^2)*(1-1/3)*(1-1/4^2)*…*(1-1/9^2)*(1/10^2) 1/1*2*3+1/2*3*4+1/3*4*5+.+1/8*9*10 因式分解；(1-1/2^2)(1-1/3^2)(1-1/4^2)...(1-1/9^2)(1-1/10^2)...(1-1/n^2) 1×2/1+1×2+2×3/1+…+1×2+2×3+3×4+…9×10/1 计算：(-2/1)+(3/1)+(-4/1)+(9/1)+(8/1)+(-9/4)=? (-1/2)+(1/3)+(-1/4)+(1/9)+(1/8)+(-4/9) = （1+1/2)*(1+1/4)*.*(1+1/10)*(1-1/3)*(1-1/5)*.(1-1/9)简算 2x+1/3-4x-1/9=1 lim(1+1/3+1/9+...+1/3^(n1))/(1+1/2+1/4+...+1/2^(n-1)) lim(1+1/3+1/9+...+1/3^(n1))/(1+1/2+1/4+...+1/2^(n-1))急