Solving Differential Equation: Find y for dy/dx = (x-y+2)/(x-y+3)

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Homework Help Overview

The discussion revolves around solving the differential equation dy/dx = (x-y+2)/(x-y+3). Participants explore various methods and substitutions to find y in terms of x.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to manipulate the equation using a substitution involving u, but expresses uncertainty about their approach. Another participant suggests a simpler substitution, u = x - y. A follow-up question is raised regarding a different form of the equation where the numerator and denominator involve different combinations of x and y.

Discussion Status

The discussion is active, with participants offering alternative substitutions and questioning the original poster's method. There is no explicit consensus, but suggestions for different approaches are being explored.

Contextual Notes

The original poster's method appears complex, and they question its validity. The follow-up question introduces a new scenario with a different differential equation, indicating a broader exploration of related problems.

Dell
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find y if

dy/dx=[tex]\frac{x-y+2}{x-y+3}[/tex]

what i tried to do was
u=[tex]\frac{x-y+2}{x-y+3}[/tex]ux-uy+3u=x-y+2

y(1-u)=x+2-u(3+x)

y=[tex]\frac{x+2-u(3+x)}{(1-u)}[/tex]y'=[tex]\frac{(1-u'(3+x)-u)(1-u)+u'(x+2-u(3+x))}{1-2u+u^2}[/tex]

[tex]\frac{(1-u'(3+x)-u)(1-u)+u'(x+2-u(3+x))}{1-2u+u^2}[/tex]=u

(1-u'(3+x)-u)(1-u)+u'(x+2-u(3+x))=u-2u^2+u^3

from here try get u's one side anx x's the other
surely this isn't the way to do this ??
 
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Try [tex]u=x-y[/tex].
 
perfect thanks
 
what would i do in a problem where the numerator and denominator have different x and y'sfor example

y'=(3x-y-9)/(x+y+1)
 

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