(1/11+1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)-(1/11+1/21+1/31+
来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/09/25 14:35:52
(1/11+1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)-(1/11+1/21+1/31+1/41+/51)*(1/21+1/31+1/41)
(1/11+1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)-(1/11+1/21+1/31+1/41+/51)*(1/21+1/31+1/41)
=【1/11+(1/21+1/31+1/41)】*(1/21+1/31+1/41+1/51)-【1/11+(1/21+1/31+1/41+/51)】*(1/21+1/31+1/41)
=1/11*(1/21+1/31+1/41+1/51)+(1/21+1/31+1/41)(1/21+1/31+1/41+1/51)-1/11*(1/21+1/31+1/41)-(1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)
=1/11*(1/51)=1/561
=【1/11+(1/21+1/31+1/41)】*(1/21+1/31+1/41+1/51)-【1/11+(1/21+1/31+1/41+/51)】*(1/21+1/31+1/41)
=1/11*(1/21+1/31+1/41+1/51)+(1/21+1/31+1/41)(1/21+1/31+1/41+1/51)-1/11*(1/21+1/31+1/41)-(1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)
=1/11*(1/51)=1/561
(1/11+1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)-(1/11+1/21+1/31+
1 {1/11+1/21+1/31+1/41}*{1/21+1/31+1/41+1/51}-{1/11+1/21+1/3
(1/11+1/21+1/31++1/41)*(1/21+1/31++1/41+1/51)-(1/11+1/21+1/3
1+11+21+31+41+51+61+71+81+9
(1/11+1/20+1/31+1/40)*(1/21+1/30+1/41+1/50)-(1/11+1/21+1/31+
(21分之1+31分之1+41分之1)*(31分之1+41分之1+51分之1)-(21分之1+31分之1+41分之1+5
1+11+21+31+41+51+61+71+81+91=
(1+11+21+31+41+51+1+71+81+91)+(9+19+29+39+49+59+69+79+89+99)
1+11+21+31+.+101+111
计算1/(6*11)+1/(11*16)+1/(16*21)+1/(21*26)+1/(26*31)+1/(31*36)
1 /6×11+1/11×16+1/16×21+1/21×26+1/26×31+1/31×36 =
26,11,31,6,36,1,41,()