Thread: Program prints out wrong result

Write a function that will for an angle x expressed in radians
calculate the approximate value of the sine function as a partial
sum of n terms of the sequence . The function receives as arguments real
number x and a positive integer n. (Do not use header <math.h> ! )


http://s33.postimg.org/c1t7ao7mn/sin_Aprox.jpg

Code:

#include <stdio.h>
#define pi 3.14159265358979323846


int fakt( int n){
	int i, fakt = 1;
	for( i = 1; i <= n; i++){
		fakt *= i;
	}
	return fakt;	
}
float degToRad( float angle1){
	float rad;
	rad = angle1 * (pi/180.0);
	return rad;
}
float pow( float base, int exponent ){
	float result = 1;
	int i;
	for( i = 1; i <= exponent; i++){
		result *= base;
	}
	return result;
}
float sinus( float deg, int numOfSeries){
	float sinusCalc = 0, angle, denominator, nominator;
	int i = 1, numOfDenom;
	angle = degToRad(deg);
	for( i = 1; i <= numOfSeries; i++){
		/*numOfDenom = 2 + i - 1;
		denominator = fakt(numOfDenom);
		nominator = pow(angle,numOfDenom);
		sinusCalc += pow(-1.0, i+1) * ( denominator/nominator); this aprroach printed out some crazy numbers*/
		sinusCalc += pow(-1.0, i+1) * ( pow(angle, (2*i-1) ) / fakt( 2*i - 1) ); 
	}
	return sinusCalc;
}
int main(void) {
	float angle,resultAngl, resultSinus;
	int n;
	printf("Enter angle in degrees and number of series: ");
	scanf("%f %d" ,&angle, &n);
	resultSinus = sinus(angle, n);
	printf("%f", resultSinus);	
 	return 0;
}

Tried to check functions fakt(),degToRad(),pow()and they are all working but in function sinus(); for example for angle = 90 degrees , and for i = 1 the result should be 1.57 and it stored 0.810569, not quite sure why this is happening.