Area Between Two Functions and the Y-Axis: How to Compute the Integral?

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Homework Help Overview

The discussion centers around computing the area between two functions, specifically f(x) = x^2 - 6 and g(x) = 6 - x^3, with a focus on integrating along the y-axis. Participants explore the implications of the problem statement regarding the bounds and the nature of the area to be computed.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to solve for x in terms of y for both functions and identifies an interception point at y = -2. They question how to compute the area given only one interception point and consider the implications of integrating from x = 0 to this point. Other participants confirm the interpretation of using x = 0 as a lower bound and inquire about the exact wording of the problem statement.

Discussion Status

Participants are actively discussing the interpretation of the problem and the correct approach to finding the area. Some guidance has been offered regarding the bounds of integration, and there is recognition of the need to clarify the problem statement further. Multiple interpretations of the area to be computed are being explored.

Contextual Notes

There is a focus on the problem's wording, particularly regarding the area bounded by the functions and the y-axis. Participants note the potential complexity introduced by the intersection points and the requirement to integrate along the y-axis.

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Homework Statement


Compute the area as an integral along the y-axis:
f(x) = x^2 - 6, g(x) = 6 - x^3

Homework Equations


N/A

The Attempt at a Solution



I solve for x in terms of y for both equations and end up with:
f(y) = +/-√(y+6), g(y) = (6-y)^(1/3)

I then look for interception points of the functions f(y) = g(y)
and I find y = -2.

My question is, if there is only one interception point how can I compute the area
between these two functions? I tried plugging into wolfram, and even it says
"cannot compute integral".

Am I reading the problem wrong? Or am I doing something wrong?

EDIT: When the question states "along the y-axis" does it perhaps mean the line x = 0 as a lower bound?
And then to just integrate from x = 0 to the point of interception (2)? That's the only way I can think of doing this.
 
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You are right when you say it means to take x=0 as a lower bound, at least that would make the most sense according to the problem statement.
 
Does the problem say something to the effect of the area bounded by the functions, f(x), g(x), and the y axis?
 
I find this question peculiar as the graphs ##f(y)## and ##g(y)## will intersect at ##(-2,2)##. This creates two different regions ( areas to compute ) in the second quadrant bounded by the line ##x=0##.

Is there more to this problem at all?
 
Yeah, it would be helpful to see EXACTLY what the problem says.
 
Verbatim:

"In Exercises 27-44, sketch the region enclosed by the curves and compute its area as an integral along the x- or y-axis."

...

28). y = x^2 - 6, y = 6 - x^3, y-axis
 
Ok, yes that says the region bounded by those two curves and the y axis, its not saying that you have to integrate with respect to y, however it would make the problem easier.
 
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