函数3.5

问题

方法

嗯，下边是自己写的。

double tsin(double x){
    double bb = x*x;
    double temp = x;
    unsigned n = 1;
    double result = 0.0;
    
    double single = temp /  factorial(n);
    while( single >= 1e-10){
        if(n % 4 == 1){
           result += single; 
       }else{
          result -= single;
        }
        temp *=bb;
         n +=2;
    }
  return result;
}

double factorial(double d){
    double result = 1.0;
    double temp = d;
    while(temp > 0){
      result *=temp;
      temp--;
}
  return result;
}

阶乘也可以用函数递归调用来处理

阶乘

double factorial(double b){
    if (b>0){
        return b * factorial(b-1);
    }
   return 1; 
}