Playing With Logs while solving y-x=5(ln|y+3|-ln|x+4|) for y.

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SUMMARY

The discussion centers on solving the separable differential equation \(\frac{dy}{dx}=\frac{xy+3x-y-3}{xy-2x+4y-8}\) to find \(y(x)\). Key techniques employed include factorization of the numerator and denominator, basic integration after variable separation, and the application of logarithmic identities such as \(e^{\ln|x|}=x\) and \(\ln|xy|=\ln|x|+\ln|y|\). The final expression derived is \(y-x=5(\ln|y+3|-\ln|x+4|)\), but there is uncertainty regarding the ability to express \(y\) explicitly as a function of \(x\), as confirmed by attempts using Wolfram Alpha.

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Homework Statement



The problem is actually the following Separable Differential Equation:
\frac{dy}{dx}=\frac{xy+3x-y-3}{xy-2x+4y-8}​
I am required to find y(x).2. Homework Equations and techniques

- factorization (applied on the numerator and the denominator in the problem equation)
- basic integration (applied after separating the variables)
- at least the following logarithmic identities:
e^{ln|x|}=x ; ln|xy|=ln|x|+ln|y|​

The Attempt at a Solution



\frac{dy}{dx}=\frac{xy+3x-y-3}{xy-2x+4y-8}

(1-\frac{5}{y+3})dy=(1+\frac{5}{x+4})dy

y-5ln|y+3|=x+5ln|x+4|+C

y-x=5(ln|y+3|-ln|x+4|)


I also put this result in Wolfram Alpha, but it could not solve the equation for y. My instructor apparently believes that an y=f(x) can be obtained. Is there any way to do so?
 
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You appear to have a sign wrong in the middle two equations, but since it comes out right at the end maybe this was a copying out error.
i don't see a way to get it into y = f(x) form either.
 
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