[hoio121]

#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
int n;
float x,y,up,down;
float c,b,sum=0,a,h;
printf("此方程式為y=ax^2+bx+c\n");
printf("請輸入係數a = ");
scanf("%f",&a);
printf("請輸入係數b = ");
scanf("%f",&b);
printf("請輸入係數c = ");
scanf("%f",&c);
printf("請輸入積分上限 = ");
scanf("%f",&up);
printf("請輸入積分下限 = ");
scanf("%f",&down);
printf("請輸入分割數n = ");
scanf("%d",&n);
h=(up-down)/(2*n);
printf("每單位寬度 = %f\n",h*2);

for(x=down;x<up;x+=2*h)
{

y=h*(a*x*x+b*x+c+a*x*x+2*x*h*a+4*h*h*a+b*x+2*h+c);
sum+=y;
}
printf("函數下的面積為 %f\n",sum);

system("PAUSE");
return 0;
}

我完成了，有需要的人可以指教