Eliminate all unit-productions from the grammar:
$S \rightarrow abA\:|\:A\:|\:B$
$A \rightarrow B\:|\:ba\:|\:aBA$
$B \rightarrow A\:|\:aa\:|\:aA$
An article I was reading said that a unit production was one whose right side consisted of exactly one variable. But this is not the case for any of these right? So is it already simplified?
When you write something like $$S \to abA\,|\, A \,|\, B$$ that is actually an abbreviation for three separate productions $$S \to abA$$ $$S \to A$$ $$S \to B$$ The last two are unit productions, since their right side consists of exactly one variable.