1 #include 
     
       2 #include 
      
        3  4 double funcos(double e, double x); 5  6 int main() 7 { 8     double e, x; 9 10     scanf_s("%lf %lf", &e, &x);11     printf("cos(%.2f) = %.6f\n", x, funcos(e, x));12 13     return 0;14 }15 16 double funcos(double e, double x)17 {18     double item = 1;19     double numerator;        //分子20     double denominator;    //分母21     double result = 0;22     int i = 0;23     double flag = 1.0;24 25     while (fabs(item) > e)26     {27         numerator = 1;28         for (int j = 1; j <= i; j++)29         {30             numerator = numerator * x;31         }32 33         denominator = 1;34         for (int k = 1; k <= i; k++)35         {36             denominator = denominator * k;37         }38 39         item = flag * numerator / denominator;40 41         result = result + item;42 43         flag = -flag;44 45         i = i + 2;46     }47 48     return result;49 50 }