### Home > CALC > Chapter 8 > Lesson 8.1.1 > Problem8-5

8-5.

Sketch the region bounded by the curve $f(x) =\sqrt { x }$ and the $x$-axis for $4 ≤ x ≤ 9$.

1. Draw a typical rectangle in the sketch and describe how the height and width are determined.

$Δx$ is the width, and $f(x+Δxi)$ is the height

2. Set up and evaluate an integral to find the area of the region.

as $Δx→0$, $f(a+Δxi)→$__________