A problem in differential equation

1. Nov 17, 2011

AlonsoMcLaren

2. Nov 17, 2011

lurflurf

by the chain rule
$$\frac{d}{dx}=\frac{\partial}{\partial x}+\frac{dy}{dx}\frac{\partial}{\partial y}$$

3. Nov 17, 2011

AlonsoMcLaren

What to do next.........

4. Nov 17, 2011

lurflurf

$$\frac{d^2 y}{dx^2}=\frac{df}{dx}=\frac{\partial f}{\partial x}+f \frac{\partial f}{\partial y}$$

the values of f and its first order partials are known from the problem statement