1/3x5十1/7x9十1/11x13十……十1/17x19_百度作业帮
1/3x5十1/7x9十1/11x13十……十1/17x19
1/3x5十1/7x9十1/11x13十……十1/17x19
原式=1/2 ×（1/3-1/5+1/5-1/7+.+1/17-1/19）=1/2 ×（1/3-1/19）=1/2 ×16/57=8/571,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,1
1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,1
摘 要： 1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,,15,16,16,17,17,18,18,18-octatriacontafluorooctadecane,Canonical SMILES: C(C(C(C(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(C(C,(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)
[Synonyms]
[Structure]
[ Properties Computed from Structure]
Molecular Weight938.131922 [g/mol]Molecular FormulaC18F38XLogP14.1H-Bond Donor0H-Bond Acceptor38Rotatable Bond Count15Exact Mass937.939322MonoIsotopic Mass937.939322Topological Polar Surface Area0Heavy Atom Count56Formal Charge0Complexity1320Isotope Atom Count0Defined Atom StereoCenter Count0Undefined Atom StereoCenter Count0Defined Bond StereoCenter Count0Undefined Bond StereoCenter Count0Covalently-Bonded Unit Count1
[ Descriptors Computed from Structure]
IUPAC Name: 1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,16,17,17,18,18,18-octatriacontafluorooctadecaneCanonical SMILES: C(C(C(C(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(C(C(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)FInChI: InChI=1/C18F38/c19-1(20,3(23,24)5(27,28)7(31,32)9(35,36)11(39,40)13(43,44)15(47,48)17(51,52)53)2(21,22)4(25,26)6(29,30)8(33,34)10(37,38)12(41,42)14(45,46)16(49,50)18(54,55)56
本文导航：
1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,1
上一篇：暂无计算：1 1/2×5+3 1/5×8+5 1/8×11+7 1/11×14+ 9 1/14 ×17+11 1/17×20 计算：一又二乘五分之一加三又五乘八加五又八乘十一分之一加七又十一乘十四分之一加九又十四乘十七分之一加十一又十七乘二十分_百度作业帮
计算：1 1/2×5+3 1/5×8+5 1/8×11+7 1/11×14+ 9 1/14 ×17+11 1/17×20 计算：一又二乘五分之一加三又五乘八加五又八乘十一分之一加七又十一乘十四分之一加九又十四乘十七分之一加十一又十七乘二十分
计算：1 1/2×5+3 1/5×8+5 1/8×11+7 1/11×14+ 9 1/14 ×17+11 1/17×20 计算：一又二乘五分之一加三又五乘八加五又八乘十一分之一加七又十一乘十四分之一加九又十四乘十七分之一加十一又十七乘二十分之一2×5,5×8,8×11,11×14,14×17,17×20是分母,1是分子.
1又1/2×5+3 1/5×8+5 1/8×11+7 1/11×14+ 9 1/14 ×17+11 1/17×20 =（1+3+5+7+9+11）+（1/2-1/5+1/5-1/8+1/8-1/11+1/11-1/14+1/14-1/17+1/17-1/19）÷3=6×6+（1/2-1/19）÷3=36+17/38÷3=36又17/114
这个1/19是怎么回事？，不是1/20吗？为什么要除以3
1又1/2×5+3 1/5×8+5 1/8×11+7 1/11×14+ 9 1/14 ×17+11 1/17×20
=（1+3+5+7+9+11）+（1/2-1/5+1/5-1/8+1/8-1/11+1/11-1/14+1/14-1/17+1/17-1/20）÷3
=6×6+（1/2-1/20）÷3
=36+9/20÷3
1/2×5=（1/2-1/5）÷3
………………………………
1/17×20=（1/17-1/20）÷31.0.3:12=2.0.25:4=3.2.8:0.7=4.2.1:1.2=5.0.1:0.8=6.7:3.5=7.1.6:0.4=8.42:21=9.36:9=10.10%:50%=11.1/2:1/4=12.1/3:1/6=13.1/4:3/4=14.1/3:1/5=15.1/9:1/6=16.5/8:1/4=17.4/7:5/7=18.5/8:5/7=19.1/5:1/10=20.2/3:3/4=21.25/10=22.15/75=23.28/4=24.51/17=25.12/75=26._百度作业帮
1.0.3:12=2.0.25:4=3.2.8:0.7=4.2.1:1.2=5.0.1:0.8=6.7:3.5=7.1.6:0.4=8.42:21=9.36:9=10.10%:50%=11.1/2:1/4=12.1/3:1/6=13.1/4:3/4=14.1/3:1/5=15.1/9:1/6=16.5/8:1/4=17.4/7:5/7=18.5/8:5/7=19.1/5:1/10=20.2/3:3/4=21.25/10=22.15/75=23.28/4=24.51/17=25.12/75=26.
1.0.3:12=2.0.25:4=3.2.8:0.7=4.2.1:1.2=5.0.1:0.8=6.7:3.5=7.1.6:0.4=8.42:21=9.36:9=10.10%:50%=11.1/2:1/4=12.1/3:1/6=13.1/4:3/4=14.1/3:1/5=15.1/9:1/6=16.5/8:1/4=17.4/7:5/7=18.5/8:5/7=19.1/5:1/10=20.2/3:3/4=21.25/10=22.15/75=23.28/4=24.51/17=25.12/75=26.12/3=27.15:21= 28.0.3/0.4=29.27:72=30.65:13= 31.45:25=32.24:144=33.0.5:2.5=34.0.5:1/3=35.1.8:2带3/5=36.1/2:8=37.4:48=38.72:48=39.6.5:13=40.1.2:36=41.6:10=42.12/22=43.100:150=44.0.4:0.5=45.3.4:0.34=46.1/20:15=47.3/4:3/5=48.3带:1/2:7=49.3:0.75=50.124:20=
1.0.3:12=1/402.0.25:4=1/163.2.8:0.7=44.2.1:1.2=7/45.0.1:0.8=1/86.7:3.5=27.1.6:0.4=48.42:21=29.36:9=410.10%:50%=1/511.1/2:1/4=212.1/3:1/6=213.1/4:3/4=1//314.1/3:1/5=5/315.1/9:1/6=2/316.5/8:1/4=5/217.4/7:5/7=4/518.5/8:5/7=7/819.1/5:1/10=220.2/3:3/4=221.25/10=2.522.15/75=1/523.28/4=724.51/17=325.12/75=4/2526.12/3=427.15:21= 5/728.0.3/0.4=3/429.27:72=3/830.65:13=5 31.45:25=9/532.24:144=1/633.0.5:2.5=1/534.0.5:1/3=3//235.1.8:2带3/5=9/1336.1/2:8=1/1637.4:48=1/1238.72:48=3/239.6.5:13=1/240.1.2:36=1/3041.6:10=3/542.12/22=6/1143.100:150=2/344.0.4:0.5=4/545.3.4:0.34=1046.1/20:15=1/30047.3/4:3/5=5/448.3带:1/2:7=1/249.3:0.75=450.124:20=31/5=6.2
自己做，实在不会的话，用计算机
用计算器自己算1十3十5十7十9十11十13十15十17十19（简便方法计算）_百度作业帮
1十3十5十7十9十11十13十15十17十19（简便方法计算）
1十3十5十7十9十11十13十15十17十19（简便方法计算）
（1+9）成10}