神马作文网(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128
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(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128
（1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)×128
=128×(1/8)[1+1/3+1/6+1/10+1/15+1/21+1/28+1/36]
=128×(1/8)[1+2(1/(2×3)+1/(3×4)+1/(4×5)+1/(5×6)+1/(6×7)+1/(7×8)+1/(8×9)]
=128×(1/8)[1+2(1/2-1/3+1/3-1/4+...+1/8-1/9]
=128×(1/8)[1+2(1/2-1/9)]
=128×(1/8)[1+1-2/9]
=128×(1/8)(16/9)
=256/9
第一步提1/8
第二步提2
第三步
1/2-1/3=1/6
1/3-1/4=1/12
1/4-1/5=1/20
1/5-1/6=1/30
1/6-1/7=1/42
1/7-1/8=1/56
1/8-1/9=1/72
=128×(1/8)[1+1/3+1/6+1/10+1/15+1/21+1/28+1/36]
=128×(1/8)[1+2(1/(2×3)+1/(3×4)+1/(4×5)+1/(5×6)+1/(6×7)+1/(7×8)+1/(8×9)]
=128×(1/8)[1+2(1/2-1/3+1/3-1/4+...+1/8-1/9]
=128×(1/8)[1+2(1/2-1/9)]
=128×(1/8)[1+1-2/9]
=128×(1/8)(16/9)
=256/9
第一步提1/8
第二步提2
第三步
1/2-1/3=1/6
1/3-1/4=1/12
1/4-1/5=1/20
1/5-1/6=1/30
1/6-1/7=1/42
1/7-1/8=1/56
1/8-1/9=1/72
（8/1+24/1+48/1+80/1+120/1+168/1+224/1+288/1）*128
（1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)×128=_____.
计算：（1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128
(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128
简算:(8/1+24/1+48/1+80/1+120/1+168/1+224/1+288/1)×128
求(1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/288)*128,请问可以套用哪种列项
（1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/228）*128
(1/8+1/24+1/48+1/80+1/120+1/168+1/224)*64=?
(1/8+1/24+1/48+1/80+1/120+1/168+1/224)*64=
(1/8+1/24+1/48+1/80+1/120+1/168+1/224)乘64
（1/8+1/24+1/48+1/80+1/120+1/168+1/224+1/228）*128 第二题：2005个9*
计算（1/8+1/24+1/48+1/80+1/120+1/168+1/224）*64