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

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SUMMARY

The discussion focuses on solving the differential equation dy/dx = (x - y + 2) / (x - y + 3). Participants explored various substitution methods, particularly using the substitution u = (x - y + 2) / (x - y + 3) to simplify the equation. The conversation highlighted the complexity of separating variables and the challenges posed by differing x and y terms in the numerator and denominator. Ultimately, the substitution u = x - y was suggested as a more effective approach for solving similar equations.

PREREQUISITES
  • Understanding of first-order differential equations
  • Familiarity with substitution methods in calculus
  • Knowledge of variable separation techniques
  • Basic algebraic manipulation skills
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  • Study the method of substitution in solving differential equations
  • Learn about variable separation techniques in differential equations
  • Explore the implications of different forms of differential equations
  • Investigate the use of integrating factors for first-order equations
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Students and professionals in mathematics, particularly those studying calculus and differential equations, as well as educators seeking effective methods for teaching these concepts.

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find y if

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

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

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

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

\frac{(1-u'(3+x)-u)(1-u)+u'(x+2-u(3+x))}{1-2u+u^2}=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 u=x-y.
 
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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