First order nonlinear ordinary differential equation

MadMathMan
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Homework Statement



y' + Ay2 = B

A & B are constants and y is a function of x

Find the general solution to the differential equation. (Find y(x)).

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The Attempt at a Solution



This differential equation came up when I was trying to solve a problem in physics. I have just learned to solve basic linear differential equations from high school and don't know how to start solving this or even if it's solvable without a computer. If somebody could give me a push in the right direction or tell me what I could study to be able to solve it, it would have been very nice :)

The only thing I've tried is differentiating it with respect to x, and getting this:

y'' + 2Ayy' = 0

I don't find this any easier because I have the y×y' there. So, any help would be nice ;)
 
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Write the ODe in the following way:
<br /> \frac{dy}{dx}=B-Ay^{2}<br />
This equation is separable, divide by B-Ay^{2} and integrate

Mat
 
This one is "separable" - which means it's solvable using integration. Rearrange to get
<br /> \frac{dy}{B-Ay^2} = dx,<br />
and do two integrals. There will be significant algebraic rearrangement involved to solve for y in terms of x.

You should probably reference a differential equations book.
 
Thanks for the answers!
That was really less painful than I expected :-p Don't know why I didn't think of that :rolleyes:
Next problem now is solving the integral, but I think I should be able to do that myself
 
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