/* lab2.c
 * A program used to integrate a function using a numerical method
 * Jeff Blair  September 11, 2006
 * */


#include <stdio.h>	
#include <math.h>	//definition of sine() function

int main (){
	double 	start,
		end,
		steps,
		area,
		delta,
		x;

	int	i;

	//Get start time, end time, and number of steps from user
	
		printf("Please enter start time:");
		scanf("%lf",&start);
		printf("\nPlease enter end time:");
		scanf("%lf",&end);
		printf("\nPlease enter number of steps:");
		scanf("%lf",&steps);

		delta = (end-start) / steps;
		
		area = 0;

		//for loop for rectangular integration
		
		for(i=0;i<=steps;i++){
		
			x = start + i * delta;
			if(x>0){
			area = area + (5 * x + (sin(9 * x - 5) / x));
			}
		}
			
		//print results to screen
		printf("\n%f\n",area);

		return 0;
}