You can use regexEquivalenceChecker.jar to compare your answers to the following solutions.

Note that when you enter a regular expression using the equivalence checker, e means ɛ. So, replace occurrences of “ɛ” in the regular expressions below with “e”.

Language 1: abb(aa)*

Language 2: (ab)*(a|ɛ)|(ba)*(b|ɛ)

Language 3: a*ba*(a*ba*ba*)*