How can I simplify these ODEs?

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Homework Statement


the first one
y'=[itex]\frac{y^{2}+xy^{2}}{x^{2}y-x^{2}}[/itex]

the second one
xyy'=[itex]\frac{x^{2}+1}{y+1}[/itex]

Homework Equations





The Attempt at a Solution


i separated x and y variable then integrate both of them

in the first one
∫[itex]\frac{y-1}{y^{2}}[/itex]dy=∫[itex]\frac{1+x}{x^{2}}[/itex]dx

ln|y|+[itex]\frac{1}{y}[/itex]+C=- [itex]\frac{1}{x}[/itex]+ln|x|+C

and the second one
∫y(y+1)dy = ∫[itex]\frac{x^{2}+1}{x}[/itex]dx

[itex]\frac{y^{3}}{3}[/itex]+[itex]\frac{y^{2}}{2}[/itex]+C=[itex]\frac{x^{2}}{2}[/itex]+ln|x|+C

but i can't change both of them into f(x) form or any simpler form
 
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It is rare that you will find a differential equation with a solution that can be written as an explicit function. Implicit solutions, the equations relating x and y that you found, are usually accepted as finding a solution to a differential equation as well. As long as there are no derivatives in your final equation, and you specify the domain of the implicit function y that is defined by your equation, where it satisfies the original differential equation, you have found a solution.
Note, however, that you do not need two constants of integration: you may condense them into a single constant: C1 - C2 = C.
 
slider142 said:
It is rare that you will find a differential equation with a solution that can be written as an explicit function. Implicit solutions, the equations relating x and y that you found, are usually accepted as finding a solution to a differential equation as well. As long as there are no derivatives in your final equation, and you specify the domain of the implicit function y that is defined by your equation, where it satisfies the original differential equation, you have found a solution.
Note, however, that you do not need two constants of integration: you may condense them into a single constant: C1 - C2 = C.

i see, i just don't really understand the difference between implicit and explicit form, so the thing i just solve is the implicit form.. thanks for answering