Pretty much just the title. Is it all possible combinations of a and b that have 2 letters ?
$\begingroup$
$\endgroup$
3
-
1$\begingroup$ Probably means $\{a,b\}^*\cdot \{a,b\}^*$ where $\cdot$ is the concatenation operation for languages. In this case, its not hard to show that $(\{a,b\}^*)^2=\{a,b\}^*$. $\endgroup$– nir shaharNov 2, 2021 at 10:44
-
1$\begingroup$ It could also mean pairs of words from $\{a,b\}^*$, e.g., $(abba,baaa)$. Depends on the context. $\endgroup$– ShaullNov 2, 2021 at 11:17
-
$\begingroup$ Don't forget that the empty string, $\epsilon$ is, for example, contained in $\{a,b\}^*$ so $(\{a,b\}^*)^2$ would also include $\epsilon, a$ and $b$. $\endgroup$– Rick DeckerNov 2, 2021 at 15:36
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
It’s not a standard way to specify a regular or any other language, so any answer would be a guess. Most likely candidates:
A string in (a, b)*, followed by another string in (a, b)*
A string in (a, b)*, followed by the same string again.
Ask whoever gave this specification for a language.
