### Home > APCALC > Chapter 1 > Lesson 1.4.2 > Problem 1-160

1-160.

The function *y* = *x*^{3} + 1 is graphed at right, along with four left endpoint rectangles which approximate the area under the curve from *x* = –2 to *x* = 2. Homework Help ✎

Why does it look like there are only three rectangles?

What happens if the left endpoint is on the

*x*-axis?Since

*f*(−1) = 0, the height of the rectangle is 0.Recall that area under the

*x*-axis is negative, while area above the*x*-axis is positive. Approximate the area under the curve for −2 ≤*x*≤ 2 using these four rectangles.Sum the areas of all four rectangles together. Remember to treat a rectangle's area as negative if it is below the

*x*-axis.