MHB Understanding the Meaning of "D_g" and "D_f" Symbols

[Petrus]

Hello MHB,
I am reading about a rule which I got no clue what it's name is on english but I think that you Will understand.

My question is what do they mean with that $$D_g$$ and $$D_f$$

Regards,
$$|\pi\rangle$$

 

[I like Serena]

Re: Understanding a symbole

My question is what do they mean with that $$D_g$$ and $$D_f$$

Looks like $D_g$ means the domain of g.
That is the set of all values of x for which g(x) is defined.

 

[Petrus]

Re: Understanding a symbole

Looks like $D_g$ means the domain of g.
That is the set of all values of x for which g(x) is defined.

Thanks! That Was what I thought aswell! Thanks for taking your time!
Regards,
$$|\pi\rangle$$