Hàm tính sinx, cosx, e^x, lnx ppt

Hàm tính sinx, cosx, e^x,lnx

[CODE="hàm tính sinx, cosx,e^x,lnxx"]#include <stdio.h>
#include <conio.h>
#include <math.h>
int menu()
{
int c;
printf("\n Menu \n");
printf("\n1. Tinh e^x = 1 + x/1! + x^2/2! + + x^n/n! + \n");
printf("\n2. Tinh sin(x) = x - x^3/3! + x^5/5! + + (-1)^n*x^(2n+1)/(2n+1)! + \n");
printf("\n3. Tinh cos(x) = 1 - x^2/2! + x^4/4! + (-1)^n*x^2n/(2n)! + \n");
printf("\n4. Tinh l(x) = (x-1)-(x-1)^2/2 + (x-1)^3/3 +(-1)^n*(x-1)^(n+1)/(n+1) + \n");
printf("\n0. Thoat");
printf("\n\n ");
printf("\nChon muc : ");
do {
c = getch();
}while (c>'4'||c<'0');
putc(c, stdout) ;
return c - '0';
}
void emux()
{
float x,e,S,gt;
int i;
printf("\nNhap vao so thuc x = "); scanf("%f",&x);
printf("\nNhap vao sai so epsilon = "); scanf("%f",&e);
i=1;
S=1;
gt=1;

while (fabs(pow(x,i)/gt) >= e)
{
S=S+pow(x,i)/gt;
i++;
gt=gt*i;
}
printf("\n Tong S = %f",S);
getch();
}
void sinx()
{
float x, s, eps, gt, t;
int i, dau;
printf("\nNhap so thuc x = "); scanf("%f",&x);
printf("\nNhap vao sai so epsilon = "); scanf("%f",&eps);
s=0.0;
gt=1.0;
i=0;
dau=1;
while (fabs(pow(x,2*i+1)/gt) >= eps)
{
s = s + dau*pow(x,(2*i+1))/gt;
i++;
gt = gt*(2*i)*(2*i+1);
dau=-dau;
}
printf("\nTong S = %f", s);
getch();
}
void cosx()

{
float x,e,S,gt,radian;
int i;
printf("\nNhap gia tri bang do cho x = "); scanf("%f",&x);
printf("\nNhap vao sai so epsilon = "); scanf("%f",&e);
radian=x*M_PI/180;
i=0;
S=0;
gt=1;
while (fabs(pow(radian,i)/gt) >= e)
{
S=S+pow(-1,i/2)*pow(radian,i)/gt;
i += 2;
gt=gt*(i-1)*i;
}
printf("\n Tong S = %f",S);
getch();
}
void lnx()
{
float x, X, s, eps;
int i, dau;
printf("\nNhap so thuc x = "); scanf("%f",&x);
printf("\nNhap vao sai so epsilon = "); scanf("%f",&eps);
X=x-1;
s=0;
i=1;
dau=1;
while (fabs(pow(X,i)/i) >= eps)
{

s = s +dau*pow(X,i)/i;
i++;
dau=-dau;
}
printf("\n Tong S = %f",s);
getch();
}
void main()
{
int chon;
do
{
chon=menu();
switch (chon)
{
case 1 : emux(); break;
case 2 : sinx(); break;
case 3 : cosx(); break;
case 4 : lnx(); break;
}
} while (chon!=0);
}[/code]