sin(3.1415938*x/180）这一步是在干什么，为什么要这样写为什么不直接写sin(x)

Question

#include "stdio.h"
#include "math.h"
int main(){
double x,y;
scanf("%lf %lf",&x,&y);
printf("sin(x):%lf\n",sin(3.1415938x/180));
printf("cos(x):%lf\n",cos(3.141593x/180));
printf("|x|:%lf\n",fabs(x));
printf("e的x次方:%lf\n",exp(x));
printf("x的y次方:%lf\n",pow(x,y));
}

Answer 1

弧度和角度的转换

sin(x) 里面的x数弧度

如果输入角度的话，需要x/180.0*3.14159