Group of Simmetries

eljose79
Let be a differntial equation which Lie group of symmetries is A..we will call this differential equation A(y,y´)

then suppose we perturbe the initial equation A with another differential operator B(y,y´) wich lie group is B.and we form the operator C(y,y´)=A(y,y´)+eB(y,y´) where e<<1 then...

what would be the lie group of simmetries for C?...

could it be obtained by perturbation theory?..