- This exercise will develop conceptual understanding.
- Explore It exercises engage students with interactive learning modules that include video and explorations. The module is also available to use for studying in the eTextbook
Review the Explore It, then use it to complete the exercise below.
Select Function 1 under the Explore & Test section of the Explore It.
When integrating with respect to the x-axis, the formula for the approximate area, using n rectangles of equal width and left end points is
Area ≈ n | |
 |
i = 1 |
(
 | xi − 1 |
− x2i − 1)
Δx.
(a)
Set the number of rectangles in the simulation to 5. What is the approximate area? (Round your answer to five decimal places.)
(b)
Set the number of rectangles in the simulation to 10. What is the approximate area? (Round your answer to five decimal places.)
(c)
What is the formula, in terms of n, for the width Δx of each rectangle? Before submitting your answer, verify your answer with various numbers of rectangles in the simulation.
Δx =
(d)
What is the formula, in terms of i and n, for the general left end point, xi − 1? Before submitting your answer, verify your answer with various numbers of rectangles in the simulation.
xi − 1 =
(e)
Using your answers to parts (c) and (d), give the general formula in terms of i and n for the approximate area when integrating with respect to the x-axis using n rectangles of equal width and left end points.
(f)
Set the number of rectangles to 2. As you increase the number of rectangles to 5, 10, 20, and 40, which rectangles give the better approximation, vertical rectangles (integration with respect to the x-axis) or horizontal rectangles (integration with respect to the y-axis)?