— Did you do your homework?
— Taken care of.
Is this a normal response or rarely used?
I wouldn't describe it as "normal" or "rare". I'd call it "niche", or possibly "trendy".
The "normal" response might be:
Yes, I took care of my homework.
However, more "terse" responses might include:
Words and phrases like this often crop up, rise in popularity, and then temper off. They often become popular among a younger demographic first. (In recent years, I've been introduced to some new and "epic" words and phrases from my kids and their friends.)
I can't remember anyone ever saying "Taken care of" when I've asked if they've completed a task (hence, I'm hesitant to call it "normal"). Yet it's not so foreign that I couldn't figure out what it meant (therefore, I wouldn't want to call it "rare," either).
A more verbose (yet equally slangy) response might include:
Yes, it is a normal use. "Taken care of" can often be given as a reply to the status of a routine task like homework.
Not to be contrary, but I don't use it as a normal response. I do, however,use such a phrase when I am in my mothering or teacher-modes...and I am both.
To me, the into,iced message is one of suggesting responsibility for a task. Otherwise, a simple, "did you... ?" should suffice.