Hi there,

In the notes I'm reading, they have stated the following PDE:

$\displaystyle u_{xx}+u_{yy}+2au_x+2bu_y+cu=d$.

Then, by defining:

$\displaystyle v(x,y)=e^{ax+by}u(x,y)$

The PDE becomes, in terms of v:

$\displaystyle v_{xx}+v_{yy}+(c-(a^2+b^2))v=e^{ax+by}d$

I don't see how they made this transformation. Should I taking partial derivatives of u as a function of v?

Thanks for your time.