Trying to solve a rather difficult differential equation

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Homework Help Overview

The discussion revolves around a differential equation modeling the interaction between two species, X and Y, represented by their fractional populations x and y, constrained by the condition x+y=1. The equation presented is \(\frac{dx}{dt}=xyA_{0}e^{-\alpha t}\), where \(A_{0}\) and \(\alpha\) are constants. Participants are exploring how to manipulate this equation to express x in terms of other variables.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants are discussing the difficulty in isolating x from the equation, particularly when it leads to a form of x/(x-1). There are mentions of using separation of variables and verifying a solution, but clarity on the algebraic manipulation remains a point of contention.

Discussion Status

The conversation reflects a mix of attempts to clarify the algebraic steps necessary to isolate x. Some participants express confusion over the readability of shared images and solutions, while others indicate progress in understanding the problem. There is no explicit consensus on the approach to take, but guidance on potential forms for manipulation has been suggested.

Contextual Notes

Participants have noted challenges with the clarity of visual aids provided, as well as the complexity of the algebraic expressions involved. The nature of the homework task appears to impose constraints on the methods that can be used to solve the equation.

RYANDTRAVERS
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Homework Statement


Consider a system composed of two species X and Y with fractional populations x and y, respectively, where x+y=1. The two species interact in such a way that the differential equation for x is:

\begin{equation}
\frac{dx}{dt}=xyA_{0}e^{-\alpha t}
\end{equation}

where $A_{0}$ and $\alpha$ are non-negative constants. Solve the equation by separation of variables and hence show that the solution for x(0) = $x_{0}$ is:

Photo attached- too long to write out!

2. The attempt at a solution

Again... attached. The problem that I am having is that I can't make x the subject of the equation because I end up with x/(x-1) on the left hand side.
 

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Last edited:
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Are you saying that you don't know how to solve that final algebraic equation for x?
 
RYANDTRAVERS said:

Homework Statement


Consider a system composed of two species X and Y with fractional populations x and y, respectively, where x+y=1. The two species interact in such a way that the differential equation for x is:

\begin{equation}
\frac{dx}{dt}=xyA_{0}e^{-\alpha t}
\end{equation}

where $A_{0}$ and $\alpha$ are non-negative constants. Solve the equation by separation of variables and hence show that the solution for x(0) = $x_{0}$ is:

Photo attached- too long to write out!

2. The attempt at a solution

Again... attached. The problem that I am having is that I can't make x the subject of the equation because I end up with x/(x-1) on the left hand side.
Those sideways images are very difficult to read.

I did use the 'Windows' snipping tool to show the solution you are to verify, then pasted it into a word processor app. & rotated it.
Capture4.PNG

Chet's got the rest.
 
Don't worry, I was a little tired last night doing a 5 hour practice paper. I've got it now... silly me.
 
Good.

To make x the subject either of the following forms might have helped.

##\displaystyle\ \frac{x}{x-1}=\frac{1}{1-1/x}=1+\frac{1}{x-1}\ ##
 

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