My Math Forum  

Go Back   My Math Forum > College Math Forum > Calculus

Calculus Calculus Math Forum


Reply
 
LinkBack Thread Tools Display Modes
September 12th, 2017, 04:37 PM   #1
Member
 
Joined: Feb 2017
From: East U.S.

Posts: 40
Thanks: 0

Disk or Washer method

Hi guys,

I'm having a little trouble setting this problem up:

"Let R be the region bounded by the following curves. Use the disk or washer method to find the volume of the solid generated when R is revolved about the‚Äč y-axis. y = x, y = 5x, y = 20"

I can solve for the volume once I have the integral set up, but I'm a little confused on how to get the boundaries, as well as which function is being subtracted from the other.

Normally I'll get two "y = ..." and two "x = ...", but I have three "y = ..." this time.

Any tips would be great!

Thank you.

Last edited by nbg273; September 12th, 2017 at 04:39 PM.
nbg273 is offline  
 
September 12th, 2017, 04:55 PM   #2
Math Team
 
Joined: Jul 2011
From: Texas

Posts: 2,624
Thanks: 1305

washers w/respect to y ...

$\displaystyle A = \pi \int_0^{20} y^2 - \left(\dfrac{y}{5}\right)^2 \, dy$
skeeter is online now  
Reply

  My Math Forum > College Math Forum > Calculus

Tags
disk, method, washer



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Washer Method mr. jenkins Calculus 6 May 14th, 2014 07:33 PM
When do I use the washer method? mortified_penguin Calculus 13 December 28th, 2012 07:02 PM
Disk/Washer Integration with ln function brsystem Calculus 4 September 16th, 2012 08:20 PM
Difference between Disk/Washer and Cylindrical Shells Obsessed_Math Calculus 4 July 6th, 2012 09:36 PM
Using the washer/shell/disk when solving in terms of y. inspiration100 Calculus 1 March 8th, 2009 12:11 PM





Copyright © 2017 My Math Forum. All rights reserved.