(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/25 22:13:30
(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)(1+1/2+1/3+···+

(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)
(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)

(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)
答:
设a=1+1/2+1/3+···+1/2003
(1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)
=a(a-1+1/2004)-(a+1/2004)(a-1)
=a(a-1)+a/2004-a(a-1)-(a-1)/2004
=a/2004-a/2004+1/2004
=1/2004

设t=1/2+1/3+···+1/2003
原式=(1+t)(t+1/2004)-(1+t+1/2004)t
=[t²+(1+1/2004)t+1/2004] - [t²+(1+1/2004)t]
=1/2004

急·····················1+2+3+...+999=? 1 2 3 4 ·····7 ·······10 ········?1 3 5 7 ·····?······?··········290 1 4 9 ·····?······?··········? 1+2++3+··········+10000= 8+11+14+17+20+·······+305 数学计算题.呜呜呜1+2+3+4+···················+98+99+100+99+98+···············+3+2+1 1/(1+2)+1/(1+2+3)+1/(1+2+3+4)+······+1/(1+2+3+······+200)=? 根据1+2+3+4+······+n=n(n+1)/2 计算2+4+6+····+200 秦始皇和汉武帝各自的功劳是?(用1·······2·······3··········来说) 证明1·3·5·····(2n-1)/2·4·6·····2n 数列 1/2,3/2,1/3 ,4/3,·········1/n+1,n+2/n+1,·········是否有极限? 已知三个角1,2,3满足:1与2互补,2与3互余,试求1-3的大小!································· 1/3+2/3=1,但0.333···+0.666···=0.999···,为神马?额······谁能解释一下······ 某大学有两栋宿舍楼,1号楼里住着200名学生,2号楼里住着300名学生.两楼相距900米.如图1号楼·············································900米·················· 1+1/(1+2)+1/(1+2+3)+·····+1/(1+2+3+·····+n) 求和 变态数学题·······方程一道············x+2y+3z=1x=y+12x+3y+5z=2方程组············要过程············我解了之后总觉得无解····· 2[4/3y—(2/3y—1/2)]=3/4y急·································!1 俗语和名句的填空1······,自知之明.2······,行必果.3工欲善其事,······.4临渊羡鱼,······.5非学无以广才,······.6······,福兮祸之所伏.7项庄舞剑,······.8······,人以群 (1-1/2)*(1-1/3)*·······*(1-1/2013)等于多少? (1+1/2+1/3+···+1/2003)(1/2+1/3+···+1/2004)-(1+1/2+1/3+···+1/2004)(1/2+1/3+···+1/2003)