[koaber]

hello,

I search a solution for f in this equation :

df/dx1+d(f*g)/dx2=0

where g=(-b22*x2-b21*x1-1)/(b12*x2+b11*x1+1) (bij are constant).

Can someone help me?

Thanks,
Yohann (from France).

[thoth]

Start be rewritting this into an easier to manage form

f_{x_{1}}+g*f_{x_{2}}+g_{x_{2}}f=0

Now this is just a standard variable coeffecient pde where the coeff. Are 1 g and g_{x_{2}}. Now solve this in terms of the coefficients and then calculate what g_{x_{2}} is to get and answer for f in terms of x_{1} and x_{2}.