Solve for the initial value of the differential equation

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jpp46656
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Homework Statement



Solve the initial value problem: y+(3x-xy+2)dy/dx = 0 , y(1)=1

I couldn't separate with y as a dependent variable, so I made x the dependent variable and I get this: dx/dy= x(1-2/y)-(2/y),
in linear standard form: dx/dy+(3/y - 1)x = -2/y.


Homework Equations





The Attempt at a Solution



You can see that I attempted the solution. I'm just wondering if I performed the steps correctly and if the answer is correct.
 
Attachments
  • Handwritten derivation on lined paper, rotated sideways, solving a first-order linear ODE by treating x as dependent on y, with an integrating factor and the general solution worked out. Continues on the back.
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  • Handwritten solution on lined paper, rotated sideways: integrating factor y^3 e^(-y) applied to a linear ODE in x, yielding x = -2(-y^2 - 2y - 2)/y^3 + c/(y^3 e^y), then substituting x(1) = 1 to find c = -9/e and the final x = -2(-y^2 - 2y - 2)/y^3 - 9e^y/(y^3 e).
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    24.3 KB · Views: 495
jpp46656 said:
I'm just wondering if I performed the steps correctly and if the answer is correct.
Did you try substituting the solution back into the given equations?