Solve Separable Equation: Interval for y(x)

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Homework Statement


Solve y'=y^2/x , y(1)=1 and give the largest x-interval on which the solution y(x) is defined.


Homework Equations





The Attempt at a Solution


dy/dx = y^{2}/x
\int dy/y^{2}= \int dx/x
y=1/(1-ln|x|)<br />

Therefore, i find intervals (\infty, e), (0,e), (- \infty , -e) where y(x) is defined.

so would the intervals to choose be (\infty, e) &amp; (- \infty , -e)??

Thanks
 
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2RIP said:
dy/dx = y^{2}/x
\int dy/y= \int dx/x

Hi 2RIP! :smile:

erm … what happened to the y2? :rolleyes:
 
Oh sorry, i was still learning how to use the latex coding and left it out. But the rest of my solution should be correct.

Thanks for pointing that out.
 
2RIP said:

Homework Statement


Solve y'=y^2/x , y(1)=1 and give the largest x-interval on which the solution y(x) is defined.

y=1/(1-ln|x|)<br />
Therefore, i find intervals (\infty, e), (0,e), (- \infty , -e) where y(x) is defined.

so would the intervals to choose be (\infty, e) &amp; (- \infty , -e)?

Hi 2RIP! :smile:

y is defined at x = 0 , isn't it?

I'm a little confused by the question … the two largest intervals are both infinite …

I suspect they mean the largest interval containing x = 1.

I'm not sure, though … :redface:
 
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