1. Find out the regular expression for the set of strings of a’s, b’s and c’s (aaa, aab, .. .. .. .., ccc).
Solution:
We have the input alphabets ∑ = {a, b, c}
Here, the resultant regular expression will denote any string from the given set (aaa, aab, .. .. .. .. , ccc). Thus, the resultant regular expression can be simply written as-
[a | b | c] [a | b | c] [a | b | c]
or,
[a + b + c] [a + b + c] [a + b + c]
or
[a ∪ b ∪| c] [a ∪ b ∪ c] [a ∪ b ∪ c]