3. Adds the rectangles, where n is the number of partitions (rectangles) Height of rectangle for each of the x-values in the interval Width of partition:

4. What Do We Do With This? If the number of partitions is allowed to approach infinity…what happens? That’s right! The rectangular approximation approaches the EXACT area under the curve! How do we do it?

6. What in the World? READ LIKE THIS: The integral, from a to b, of f(x) with respect to x

7. What’s With This Thing? Integral sign (originated from the summation sign, Sigma) Lower (left) limit of integration Upper (right) limit of integration Integrand (between the integral sign and the dx) Tells you the variable of integration (who is the variable)

8. The integral, from 1 to 4, of x 2 with respect to x is 21