# Assistance Solving a Non-Linear PDE

• Nov 19th 2012, 02:13 PM
MrG
Assistance Solving a Non-Linear ODE
I'm trying to find a general solution to:

$\displaystyle \frac{dy}{dx} = -A + \frac{f(x)}{y}$

where:

$\displaystyle f(x) = \frac{B}{(1+Cx)^2}$ , and the domain is [0,100], and C * x is above 1...

A, B, & C are constants...

I've tried several various substitutions to try and solve this, but feel exhausted in attempts and am looking for suggestions.
• Nov 19th 2012, 03:26 PM
topsquark
Re: Assistance Solving a Non-Linear PDE
Quote:

Originally Posted by MrG
I'm trying to find a general solution to: dy/dx = -A + f(x) / y

f(x) = B / ( 1 + Cx )^2, and the domain is [0,100], and C * x is above 1...

A, B, & C are constants...

I've tried several various substitutions to try and solve this, but feel exhausted in attempts and am looking for suggestions.

Is this supposed to be
$\displaystyle \frac{dy}{dx} = \frac{-A + f(x)}{y}$

If that's the case the equation is separable.

By the way, this is an ordinary differential equation, not a PDE.

-Dan
• Nov 19th 2012, 03:29 PM
MrG
Re: Assistance Solving a Non-Linear PDE
Quote:

Originally Posted by topsquark
Is this supposed to be
$\displaystyle \frac{dy}{dx} = \frac{-A + f(x)}{y}$

If that's the case the equation is separable.

By the way, this is an ordinary differential equation, not a PDE.

-Dan

Thank you for the reply... it is supposed to be:

$\displaystyle \frac{dy}{dx} = -A + \frac{f(x)}{y}$