c++编写程序计算下列公式的值:y = x - x^3/3! + x^5/5! - x^7/7! + ⋯,精确到第n项,其中n = 10,x = 2.5分别由键盘输入。(答案:0.598472)

#include <stdio.h>
#include <math.h>

int main() {
int n;
double x, y = 0, fac = 1;
printf("请输入n和x的值：\n");
scanf("%d %lf", &n, &x);
for (int i = 1; i <= n; i++) {
fac *= i; //计算i的阶乘
if (i % 2 == 1) { //奇数项
y += pow(x, 2*i-1) / fac;
} else { //偶数项
y -= pow(x, 2*i-1) / fac;
}
}
printf("y的值为：%.6f\n", y);
return 0;
}

相关问题

C++编写程序计算下列公式的值：y = x - x^3/3！+ x^5/5！- x^7/7！+ ⋯，精确到第n项

#include <stdio.h>
#include <math.h>

double factorial(int n) {
double result = 1;
for (int i = 1; i <= n; i++) {
result *= i;
}
return result;
}

double calculate(double x, int n) {
double result = x;
int sign = -1;
for (int i = 2; i <= n; i += 2) {
double term = pow(x, i) / factorial(i);
if (sign == -1) {
result += term;
} else {
result -= term;
}
sign = -sign;
}
return result;
}

int main() {
double x;
int n;
printf("请输入x和n：");
scanf("%lf %d", &x, &n);
double y = calculate(x, n);
printf("y = %lf", y);
return 0;
}

c++编写程序计算下列公式的值:y=x-x^3/3!-x^5 /5!+x^7/7! …,精确到第n项sad

好的，以下是C++代码实现，可以计算公式y=x-x^3/3!-x^5 /5!+x^7/7! …的前n项，并精确到小数点后10位：

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

double calcFactorial(int n){
    double res = 1.0;
    for(int i=2; i<=n; i++){
        res *= i;
    }
    return res;
}

double calcPower(double x, int n){
    double res = 1.0;
    for(int i=1; i<=n; i++){
        res *= x;
    }
    return res;
}

double calcY(double x, int n){
    double res = x;
    double sign = -1.0;
    for(int i=1; i<=n; i++){
        double term = sign * calcPower(x, 2*i-1) / calcFactorial(2*i-1);
        res += term;
        sign = -sign;
    }
    return res;
}

int main(){
    double x;
    int n;
    cin >> x >> n;
    double y = calcY(x, n);
    cout.precision(10); //设置输出精度为小数点后10位
    cout << y << endl;
    return 0;
}

你可以输入x和n的值，程序会计算出公式的前n项，并输出结果。