Calc 2 Integration Area Problem

Click For Summary

Homework Help Overview

The discussion revolves around a calculus problem involving the integration of the area between the curves defined by the equations y=3-x^2 and y=x+1. Participants are attempting to find the area of the region bounded by these curves.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants are discussing the setup of integrals to find the area, with some suggesting the use of vertical versus horizontal integration. There are questions about the correctness of the original poster's attempts and the assumptions made regarding the limits of integration.

Discussion Status

There is an ongoing exploration of the problem, with some participants providing guidance on the integration approach and questioning the assumptions made about the variables involved. The original poster's attempts have been noted as incorrect, prompting further inquiry into their reasoning.

Contextual Notes

Participants have noted that the images provided by the original poster are not readable, which may hinder the discussion. Additionally, there is a mention of guidelines for students and helpers that may influence the nature of the responses.

Alexa
Messages
4
Reaction score
0

Homework Statement


Please help me solve the calc problem pictured!

Homework Equations


y=3-x^2 and y=x+1

The Attempt at a Solution


My attempt is in one of the photos!
 

Attachments

  • Screen Shot 2018-05-16 at 4.43.41 PM.png
    Screen Shot 2018-05-16 at 4.43.41 PM.png
    27.8 KB · Views: 500
  • Screen Shot 2018-05-16 at 4.43.35 PM.png
    Screen Shot 2018-05-16 at 4.43.35 PM.png
    15.4 KB · Views: 577
Physics news on Phys.org
Alexa said:

Homework Statement


Please help me solve the calc problem pictured!

Homework Equations


y=3-x^2 and y=x+1

The Attempt at a Solution


My attempt is in one of the photos!
Type the problem statement, and your solution. Your images are not readable on my devices, and so I am unable to help or give hints.

For more on this issue, see the post "Guidelines for students and helpers", by Vela.
 
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system
 
Alexa said:
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system

So, the problem statement is asking you to find the area the hard way; integrating with respect to ##x## would be a lot easier.

Anyway, to see the ##x##-limits in the ##y##-integrals, you should start by drawing a picture of your region. The first (vertically lower) region goes from a negative value of ##y## to a positive value, and for each such ##y##, from a smaller (sometimes negative, sometimes positive) value of ##x## to a larger value of ##x##---giving a positive ##x##-length. You have your first integral going from a large value of ##x## to a smaller one---giving a negative ##x##-length.

You seem to be assuming that ##x## must be positive, but that is not stated anywhere in the problem as you wrote it.
 
Alexa said:
The region R is bounded by y=3−x^2 and y=x+1.
The area of the region can be found by integrating: integral from 1 to 2 ______dy + integral from 2 to 3 ______dy
For the first blank I had (sqrt(3-y))-(y-1) and for the second I had (sqrt(3-y)-2)
These are both wrong according to the system
Could you explain to us how you came up with your attempt?
 

Similar threads

Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
4
Views
3K
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
1
Views
2K