c·z家具

已知a/x+b/x+c/x=0,x/a+y/b+z/c=1,求证x·x/a·a+y·y/b·b+z·z/c·c...

题目错了吧，应该是a/x+b/y+c/z=0 x/a + y/b + z/c =1 (x/a + y/b + z/c)^2 =1 x·x / a·a + y·y / b·b + z·z / c·c+2(xy/ab+xz/ac+yz/bc)=1 x·x / a·a + y·y / b·b + z·z / c·c+2(xyz/abc) *(a/x+b/y+c/z)=1 因为a/x+b/y+c/z=0 所以原式为x·x / a·a + y·y / b·b + z·z / c·c=1

编写C程序,题目：如果令A、B、C、D······Z分别等于1,2·...

#include int num( char *s ){int sum=0;while( *s ){if ( *s >='A' && *s sum += *s-'A'+1 ;s++;}return sum;}int main(){char s[100];gets(s);printf(＂%s=%d%%\n＂, s, num(s) );return 0;}

x+y+z=14,x'+y'+z'=15,(x

num=0;for a=2:1:9for b=2:1:9for c=2:1:9for d=2:1:9if a^b*c^d==1000*a+100*b+10*c+dnum=num+1;an(num,1)=a;an(num,2)=b;an(num,3)=c;an(num,4)=d;endendendendend>>anan =2 5 9 2>>电脑算出来的可以么？a=2,b=5,c=9,d=2

直线x=y=(z

单个字母转化：#includeint main(){char a;while((a=getchar())!=EOF){getchar();if('A'a='Z'-a+'A';putchar(a);putchar('\n');}return 0；}字符串转化：#includeint main(){int i;char a[1000];while(gets(a)){for(i=0;a[i]!='\0';i++)if('A'a[i]='Z'-a[i]+'A';puts(a);}return 0;}...