//Vi?t S(x, n) = 1 + x^2/2! + x^4/4! + ... + x^2n/(2n)!
#pragma warning (disable :4996)
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
void Input(int &x,int &n);
void output(int x,int n);
int Giaithua(int n);
float LuyThua(int x,int n);
float Tong(int x,int n);
int main()
{
	int n;
	int x;
	Input(x,n);
	output(x,n);
	system("pause");
	return 0;
}
void Input(int &x,int &n)
{
	printf("Nhap x = ");
		scanf("%d",&x);
	printf("Nhap n = ");
		scanf("%d",&n);
}
int Giaithua(int n)
{
	int GT = 1;
	if(n==0)
	return 1;
	else
	{
		for(int i= 1;i<=n;i++)
			{
				GT = GT * i;
			}
	}
	return GT;
}
float LuyThua(int x,int n)
{
	float P = pow(x,n);
	return P;
}
float Tong(int x,int n)
{
	float S = 0;
	for(int i = 0;i<=n;i++)
	{
		S = S +(float) LuyThua(x,2*i)/Giaithua(2*i);
	}
	return S;
}
void output(int x,int n)
{
	float kq = Tong(x,n);
	printf("Ket qua la : %0.2f\n",kq);
}