Taylor series- C

Question

Can someone help me?

https://i.stack.imgur.com/X3KAr.png

I need to make this code work... But the fatorial wont work correctly...

code:

#include <stdio.h>
#include <math.h>

int main()
{
double x, z = 0, fat = 1;
int n, i, j, fat2=0;
scanf("%lf%d", &x, &n);

j = 1;

for(i = 0; i < n; i++ )
{
//printf("\n%d :: %lf :: %d ", fat2, fat, i); // DEBUG

z = z + ( ( pow(-1 , i)*pow(x, (2*i)) ) / (fat) );

fat2 = 2*j;
fat = fat * (fat2 - i);

j++;
}
printf("\ncos(x) = %lf\n", z);

return 0;
}

Thanks!

Answer 1

you can put this on code play ground for proper editing, will look into it now

edited: a factorial function will look like this N*(N-1)
my advise for you to debug this, create a function for factorial and call it in the equation you need it

Answer 2

Ty for the help.
Solved!
https://code.sololearn.com/c8sjtA4hj7DG