每日一题——第六十八题

题目：计算sinx = x - x^3 / 3! + x^5 / 5!+… + (-1) ^ (n + 1) * x ^(2 * n - 1) / ((2 * n - 1)!)

#include<stdio.h>
#include<math.h>
long long CalculateFactorical(int n);
int main() {int x = 2;float sum = 0.0;//考虑精度要求，取 n = 10for (int n = 1; n <= 10; n++){sum += pow(-1, n + 1) * pow(x, (2 * n - 1)) / CalculateFactorical(2 * n - 1);}printf("sin%d = %lf", x, sum);//这里为了方便演示，求sin2的值return 0;
}/// <summary>
/// 计算n！
/// </summary>
/// <param name="n"></param>
/// <returns></returns>
long long CalculateFactorical(int n) {if (n < 0) return 0;if (n == 0) return 1;if (n > 0) return n * CalculateFactorical(n - 1);}