#include<iostream> |
using namespace std; |
void main() |
{ |
double n=1,i=1,j=1,N,x,s=1; |
double t=1.0,sum=0; |
cout<< "请输入一个x的值:" <<endl; |
cin>>x; |
cout<< "输入一个N的值" <<endl; |
cin>>N; |
while (i<=N) |
{ |
i++; |
sum=sum+t; |
t=(j/n)*s; |
s=-s; |
j=j*x; //X的i次方 |
n=n*i; //i的阶乘 |
} |
cout<< "前" <<N<< "项和为" <<sum<<endl; |
} |