(my blank space is to let you see the title better, and it is required to make simple calculation! I am very urgent! Do as much as you can.) 1. 1 + 2 of 1 + 1 + 2 + 3 of 1 + 1 + 2 + 3 + 4 of 1 + 1+2+… One in 99= 2. (1 / 11 + 1 / 21 + 1 / 31 + 1 / 41) * (1 / 21 + 1 / 31 + 1 / 41 + 1 / 51) - (1 / 11 + 1 / 21 + 1 / 31 + 1 / 41 + 1 / 51) * (1 / 21 + 1 / 31 + 1 / 41 + 1 / 51)= 471471471471÷157157157157= | Math enthusiast | Mathematical art

(my blank space is to let you see the title better, and it is required to make simple calculation! I am very urgent! Do as much as you can.) 1. 1 + 2 of 1 + 1 + 2 + 3 of 1 + 1 + 2 + 3 + 4 of 1 + 1+2+… One in 99= 2. (1 / 11 + 1 / 21 + 1 / 31 + 1 / 41) * (1 / 21 + 1 / 31 + 1 / 41 + 1 / 51) - (1 / 11 + 1 / 21 + 1 / 31 + 1 / 41 + 1 / 51) * (1 / 21 + 1 / 31 + 1 / 41 + 1 / 51)= 471471471471÷157157157157=

1、 = 1 + 1 / 2 + 1 / 6 + 1 / 10 + +1/4950 ＝1+1/2+（1/12+1/20+… +1/9900）*2 ＝1+1/2+（（1/3-1/4）+（1/4-1/5）… +(1 / 99-1 / 100)) * 2 = 1 + 1 / 2 + (1 / 3-1 / 100) * 2 = 1 + 1 / 2 + 97 / 150 = 161 / 75 2. Let (1 / 21 + 1 / 31 + 1 / 41) be a, let (1 / 11

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