I always have trouble finding my "k" value for error bounds when doing approximation of integrals. With Trapeziodal and Midpoint error bounds, I take the second derivative of my function. Then I find the number on the interval (between limits of integration that I am given) that will give me the biggest output when plugged into f ''(x). I run that through the f '' (x) function and the number that results is my "k". With Simpson's, I know the 4rth derivative is used - but is it the same technique? Am I looking for the maximum output I can get from the 4rth derivative using a value from my limits of integration? In which case, should I be taking the 5th derivative as well to determine maxima on the interval for my fourth derivative function? I hope this makes sense. My brain is starting to meltdown from studying for midterms. :yuck: Thanks in advance.