Question

计算级数s=1+x+x^2/2!+x^3/3!+···+x^n/n!.并编写main函数调用sum函数

Answer 1

#include <stdio.h>

double sum(double x, int n)
{
double s = 1;
int i;
double t = 1;
double a = 1;
for(i=1;i<=n;i++)
{
a*=x;
s+=a/t;
t*=i+1;
}
return s;
}

int main()
{
int n;
double x;
while(scanf("%lf%d",&x, &n)==2)
{
printf("%lf\n",sum(x,n));
}
}

追问

以下是sum函数的功能是计算级数s=1+x+x^2/2!+x^3/3!+···+x^n/n!.补全程序，并编写main函数调用sum函数 计算当x=1.5 n=20时s的值
double sum(double x,int n)
{
int i; double a,b,s;
/*给函数中各变量正确付初值*/
for(i=1;i<=n;i++)
{a=a*x; b=b*i; s=s+a/b;}
return s;
}
帮忙拜托啦

追答

double sum(double x,int n)
{
int i; double a,b,s;
s=1;a=1;b=1; /*给函数中各变量正确付初值*/
for(i=1;i<=n;i++)
{a=a*x; b=b*i; s=s+a/b;}
return s;
}