#include"iostream.h"
#include"math.h"
int jiecheng(int x)
{
    int j,k;
    for(j=1,k=1;j<=x;j++)
        k=k*j;
    return k;
}
double fun(double x,double eps=1e-6)
{
    double s;
    int i;
    for(i=1,s=x;pow(x,2*i+1)/jiecheng(2*i+1)>eps;i++)
    {
        s=s+pow(-1,i)*pow(x,2*i+1)/jiecheng(2*i+1);
    }
    s=s+pow(-1,i)*pow(x,2*i+1)/jiecheng(2*i+1);
    return s;
}
void main()
{
    double x;
    cout<<"Input x please    x=";
    cin>>x;
    cout<<'\n'<<fun(x)<<'\n';
}

各位好人幫幫忙啊

在线等求帮忙

冒个泡，你哪里有问题，我帮你

for(i=1,s=x;pow(x,2*i+1)/jiecheng(2*i+1)>eps;i++)
    {
        s=s+pow(-1,i)*pow(x,2*i+1)/jiecheng(2*i+1);
    }
    s=s+pow(-1,i)*pow(x,2*i+1)/jiecheng(2*i+1);

s=s+pow(-1,i)*pow(x,2*i+1)/jiecheng(2*i+1);最后一句去掉，你写两句干吗？

#include<stdio.h>
#include<math.h>
double eps=0.000001;
double cheng(int x)
{
    int j;
double k;
    for(j=1,k=1;j<=x;j++)
        k=k*j;
    return k;
}
double fun(double x)
{
    double s=x,u=1;
    int i;
    for(i=1;u>eps;i++)
    {
u=pow(x,2*i+1)/cheng(2*i+1);
        s=s+pow(-1,i)*pow(x,2*i+1)/cheng(2*i+1);
    }
    s=s+pow(-1,i)*pow(x,2*i+1)/cheng(2*i+1);
    return s;
}
void main()
{
    double x;
    scanf("%lf",&x);
    printf("%lf\n",fun(x));
}

代码格式请注意，fun函数第二个S赋值就删了吧，还有fun函数在main里面要修改下

pow（-1，i）会出现重载错误，添加double a=-1，再使用pow（a，i）

#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    float sum, term, x;
    int sign = 1, k = 2;
   
    cout << "Please input x:" << endl;
    cin >> x;

    sum = x;
    term = x;            
   
    while ( fabs(term) >= pow(10, -6) ) {
        k = 2 * k - 1;
        term *= x * x / k / ( k - 1）;
        sign = -sign;
        sum += sign * term;
    }
    cout << sum << endl;

    return 0;
}

[ 本帖最后由 荡气回肠 于 2012-5-16 21:19 编辑 ]