Solving Exact Diff. Eq: Finding Integral Curves

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The discussion focuses on solving the exact differential equation y'=(y+x)/(y-x) and finding its integral curves. The user successfully derived the implicit solution, reaching the equation (y^2/2) - (x^2/2) - yx = constant. They seek clarification on how to graph the integral curves since they cannot express y explicitly in terms of x. Suggestions include choosing specific constant values to graph the curves, leading to the discovery of multiple solutions for fixed constants. The user confirms that for a constant C, they obtain two curves, hinting at the possibility of parabolic or hyperbolic shapes.
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Homework Statement


Find the solution to y'=\frac{y+x}{y-x} and graph the integral curves.

Homework Equations


Exact differential equation.

The Attempt at a Solution


I noticed it's an exact differential equation, I solved it implicitely. I reached that \frac{y^2 (x)}{2}-\frac{x^2}{2}-yx=\text{constant}. I've looked into wikipedia about the integral curves but I don't really know how to find them here. If I understood well, an integral curve is a solution to the DE, so here it would be any y(x) that satisfies the DE. But here I can't get y(x) explicitely, so how do I graph y(x)?... Any idea is welcome!
 
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Choose a number of specific values for the constant and graph those curves.
 
HallsofIvy said:
Choose a number of specific values for the constant and graph those curves.

Ah I see, thank you very much. I graph point per point, maybe I'm missing an obvious curve or something.
I take C=1. I set x=0 and I get y=\pm \sqrt 2. I graph this in the x-y plane. Now I set x=2 and I get a quadratic equation for y, which yields y= 2 \pm \sqrt {10}. So for a fixed C, there are 2 curves; maybe parabolas or hyperbolas.
 
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