Approximating area of a plane region caught between the curve and the x-axis over an interval.

We know how to find the area of triangles, rectangles, trapezoids, circles, etc from our geometry formulas, but what if we want to find the area of a region that has curved sides? To lay the foundation for the process of finding the actual area, we will first look at approximating the area using rectangles of equal width. This video covers an example for approximating the area between f(x)=x^2 + 1, the x-axis, over the interval [-1,1] using n=4 rectangles, and the cases of right endpoints then left endpoints. For the video using midpoints, click on:
How do you approximate area between a curve and the x-axis on an interval?
• How do you approximate...