Hi Folks,

Semi Linear PDE

A book book gives a linear first order PDE in the form

a(x,y)u_x+b(x,y)u_y+c(x,y)u=f(x,y)

My lectures notes has a 'semi linear' PDE in the form

a(x,y)u_x+b(x,y)u_y=h(x,y,u)

The presence of u on the RHS makes the PDE semi linear however where does the independant variable u itself disappear in the second equation?

Thanks