问题描述

三角函数tanpi怎样计算

为什么在Vc++6.0中 tan 3.1415926 = -0

解决方案

在几何知识中tan(180) = 0，如下图所示;

解决方案二：

 //THE PROGRAM IS TO TELL YOU HOW TO USE
//THE MATH.H LIBRARY .
//FILE MATH.CPP   

#define HUNDRED 100
#include  <stdio.h>
#include  <conio.h>
#include   <math.h>   

int main(void)
{
    double CIRCLE,PI,VALUE;
    printf("n     -*-*- THE MATH FUNCTIOIN 'SIN()' & 'COS()'& 'TAN()'-*-*-n");
    printf("nTHE DEGREE");
    printf("   THE SIN() VALUE");
    printf("     THE COS() VALUE ");
    printf("     THE TAN() VALUE n");
    PI=3.1415926;
    for (CIRCLE=0;CIRCLE<HUNDRED;CIRCLE+=10)
    {
        VALUE=CIRCLE*PI/180;
        printf("%2d",(int)CIRCLE);
        printf("         %6.4f",sin(VALUE));
        printf("         %6.4f",cos(VALUE));
        printf("                     %6.4f",tan(VALUE));
        printf("n");
    }
    getch();
    return 0;
}