作业帮2*2 22*22 222*222
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/12 13:48:44
2=2*(1+0)22=2*(11+0)以些类推2222222=2*(1111111+0)=2*(1+11+111+1111+11111+111111+1111111)=2*1234567
#includevoidmain(){inta,sn=0,tn=0,i,n;clrscr();scanf("%d,%d",&a,&n);i=1;while(i
aa...a(n个)=a*10^(n-1)+a*10^(n-2)+……+a*10^1+a*10^0这是以a为首项,10为公比的等比数列,有n项=a*(1-10^n)/(1-10)=a*10^n/9-a
#includevoidmain(){inti,sum=0,a=2;for(i=0;i
#includevoidmain(){longinti,j,a,n,Sn=0;scanf("%ld%ld",&a,&n);j=a;for(i=1;i
第二次循环时,a=22*10+22=242.稍改一下#include"stdio.h"main(){longs=0;inta,b,N,i;printf("EntertheaandN:\n");/*N是
main(){inta,n,count=1;longintsn=0,tn=0;printf("pleaseinputaandn\n");scanf("%d,%d",&a,&n);printf("a=%
inta,n;doublesum=0;scanf("%d%d",&a,&n);for(sum=a,i=2;i
应该这样写：#include#includevoidmain(){inti,n,sum;sum=0;i=2;for(n=1;n
#includeintmain(){inti,j,sum=0;for(i=2,j=0;jprintf("%d\n",sum);return0;}
2+22+222+2222+22222=2×（1+11+111+1111+11111）=2×12345=24690再问：谢谢罗
2+22+222+2222+22222+-------+2222222222=2(1+11+111+...+111111111+1111111111)=2(123456789+1111111111)=
#includemain(){inta=2,b,c,sum=0;for(b=1;
9#5=5+55+555+5555+55555+555555+5555555+55555555+555555555=5*9+50*8+500*7+5000*6+50000*5+500000*4+500
2*2=422*22=484222*222=492842222*2222=493728422222*22222=493817284222222*222222=49382617284后边是284
解题思路：点的坐标的问题解题过程：varSWOC={};SWOC.tip=false;try{SWOCX2.OpenFile("http://dayi.prcedu.com/include/readq
答案应该是2乘以i乘以10的（n-i）次方这样形式数的和,i是从1到n然后求上面那个数列的和求上面数组的和应该是高中学过的东西,令Sn为前n项的和,写出它的展开式写出10*Sn的展开式用10*Sn-S