• Support PF! Buy your school textbooks, materials and every day products Here!

Integration for Volume Given Cross Sections

  • #1

Homework Statement



The roof and walls of a storage building are built in the shape modeled by the curve y(x) = 20 - [tex]\frac{x^6}{3,200,000}[/tex]. Each cross section cut perpendicular to the x-axis is a rectangle with a base of 50 feet and a height of y feet.

In cubic feet the volume of the building is approximately:

A) 686
B) 2,000
C) 17,100
D) 34,300
E) 50,000

Homework Equations



Area = (50)(y(x)) = 50 ( 20 - [tex]\frac{x^6}{3,200,000}[/tex] )

The Attempt at a Solution



Given the equation above, I reasoned that the area is the base (the 50 feet) multiplied by the function y(x). I carried the following integration:

V = [tex]\int^{0}_{20}[/tex] 50 * ( 20 - [tex]\frac{x^6}{3,200,000}[/tex] )

I get an answer of 17142.86. Is this correct? It's a little off from the problem.
 

Answers and Replies

  • #2
Dick
Science Advisor
Homework Helper
26,258
618
Sure it's right. If you look at the answers they are described as 'approximate' and appear to all be rounded to three significant figures. If you round your answer it certainly matches C).
 
  • #3
Thank you!
 

Related Threads for: Integration for Volume Given Cross Sections

Replies
1
Views
3K
Replies
5
Views
3K
Replies
1
Views
1K
  • Last Post
Replies
8
Views
1K
  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
11
Views
3K
  • Last Post
Replies
2
Views
1K
Top