### Home > CALC > Chapter 7 > Lesson 7.3.1 > Problem 7-115

7-115.

**Multiple Choice:**Find the area of the largest rectangle that can be inscribed under the graph of*y*= cos*x*, in the interval −*≤ x ≤*. 7-115 HW eTool (Desmos). Homework Help ✎1.10

1.12

1.14

1.16

1.18

Let (*a*, 0) be the coordinate of the lower right-hand vertex. What will be the coordinates of the other three vertices?

Write an equation for the area of this rectangle, in terms of *a*. Then optimize it.

Use the eTool below to help solve the problem.

Click the link at right for the full version of the eTool: Calc 7-115 HW eTool