Differential Equations - Find equation of line

qw111
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Homework Statement



A curve passing through (3,-2) has a slope given by (x^2 + y^2)/(y^3 - 2xy). Find the equation of the curve.

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The Attempt at a Solution



My first thought was to plug in the points (3,-2) into the slope equation and plug them into the line equation (y - y1) = m(x - x1). Is that wrong? Seemed too easy for it to be a problem for differential equations..

So, I found that i could make the slope equation into an exact equation and solved for it.
I found that the answer i get is:
with c = -17
f(x,y) = x^3/3 + xy^2 - y^4/4 - 17
However that is not the equation of the curve. Is that the equation of the tangent line at (3,-2)?
I am stuck at this point, I am pretty sure I am done with 90% of the work, but I can't seem to figure out the equation of the curve from here on.
 
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Yes, you are pretty close, but you faltered a bit at the end.

The equation you were solving looked something like this:
Fx dx + Fy dy, where Fx = x2 + y2 and Fy = -y3 + 2xy

The solution to the equation above with the partials is F(x, y) = C, so you should have gotten (1/3)x3 - (1/4)y4 + xy2 = C.

Substitute y(3) = -2 into the equation above to find the constant C.
 
Yes I did that, realized that C = 17 (not negative). But I am still puzzled, what is the equation of the curve?
 
(1/3)x3 - (1/4)y4 + xy2 = 17.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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