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koaber
Apr 10, 2006, 01:55 AM
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
Apr 15, 2006, 11:02 PM
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}.