How to Get Rid of Natural Logarithms in Separable Differential Equations

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SUMMARY

The discussion focuses on solving the separable differential equation dy/dx=(xy+3x-y-3)/(xy-2x+4y-8). The user successfully factored the equation and separated variables to obtain (y-2)/(y+3) dy = (x-1)/(x+4) dx. Upon integrating, the user arrived at y-5*ln(y+3) = x-5ln(x+4) but struggled with eliminating the natural logarithms. A suggestion was made to exponentiate both sides of the equation to correctly handle the logarithmic terms.

PREREQUISITES
  • Understanding of separable differential equations
  • Knowledge of integration techniques
  • Familiarity with logarithmic and exponential functions
  • Ability to manipulate algebraic expressions
NEXT STEPS
  • Review the process of exponentiating both sides of an equation
  • Study techniques for solving separable differential equations
  • Learn about the properties of logarithms and exponentials
  • Practice additional examples of differential equations to reinforce concepts
USEFUL FOR

Students studying differential equations, mathematics educators, and anyone seeking to improve their problem-solving skills in calculus.

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Homework Statement



so here's my equation:

dy/dx=(xy+3x-y-3)/(xy-2x+4y-8)

so what i did first was factor out the right side

=(x+1)(y-3)/(x+4)(y-2)

then i did a bunch of manipulation to get the ys on one side and the xs on another (i won't write this out right now but if anyone wants me to i can)

and got

(y-2)/(y+3) dy = (x-1)/(x+4) dx

of course i integrate, i get

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

i want to get rid of the lns, right? so i multiplied them by e (like e^(ln(y+3)

then i got -4y-15=-4x-20

i'm not sure what to do after this because i looked at the answer at the back of my book and it said something completely different to what I've done so far, any help?



Homework Equations





The Attempt at a Solution

 
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Shouldn't your exponent for [itex]e[/itex] be the entire expression on each side of the equation?

i.e.

[tex]e^{y-5ln(y+3)}=e^{x-5ln(x+4)}[/tex]
 

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