1/1+(1/2-2/1)+(1/3-2/2+3/1)+(1/4-2/3+3/2-4/1)+.+91/9-2/8=3/7
(1) 1,1/3,1/5,1/7,1/9 (2)- 1/2*1,1/2*2,- 1/2*3,1/2*4,-1/2*5
(2+1)(2^2+1)(2^3+1)(2^4+1))(2^5+1)(2^6+1)(2^7+1)(2^8+1)(2^9+
1/(1*2)+2/(1*2*3)+3/(1*2*3*4)+.+8/(1*2*3*4*5*6*7*8*9)=?
1/1+(1/1+2)+(1/1+2+3)……+(1/1+2+3+4+5+6+7+8+9+10+11)=
2(3+1)(3^2+1)(3^3+1)(3^4+1)(3^8+1)+1
1:8 2:9 1:9 3:4 1:3 ...
1/1×2+1/1-1/2:;1/2×4=1/2×(1/2-1/4);1/58×=1/3(×1/5-1/8)
(1-1/2^2)(1-1/3^2)(1-1/4^2)(1-1/5^2)(1-1/6^2)(1\1/7^2)(1-1/8
1/1*2*3+1/2*3*4+1/3*4*5+.+1/8*9*10
计算:1+1/1+2+1/1+2+3+1/1+2+3+4+…+1/1+2+3+4+5+6+7+8+9+10(过程)
1+(1/1+2)+(1/1+2+3)+(1/1+2+3+4)+~+(1/1+2+3+4+5+6+7+8+9+~+199
1/2-(3/4-3/8), 1/2+1/4-1/6 , 2/3+(1/2+1/4),