Is the Midpoint Rule Different from Simpson's Rule?

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Homework Statement


I'm working on a practice test and got stuck on the question: Approximate the length of the curve y=√x, 0≤x≤1 by the midpoint rule with n=4 and ∆x=0.25.


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Is the midpoint rule the same thing as Simpson's rule? I don't remember going over the midpoint rule in class and I can't find it in the book. If it isn't the same as Simpson's rule, what is it?
 
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I would guess that in finding the length of a curve by the midpoint rule, you calculate the function value at the midpoint of each subinterval, and then calculate the lengths of those line segments that join those points. For the approximate arc length, just add those lengths together.
 
No, the midpoint rule is not the same as Simpson's rule. With Simpson's rule, you approximate the curve by a series of parabolas through each set of 3 points.

As Mark44 says, the midpoint rule uses the midpoint of each interval to compute the height of a rectangle on that interval.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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