For each problem below (except #8), show a regular expression representing the described set. The set...

Question

Question

For each problem below (except #8), show a regular expression representing the described set.

The set of strings over {c, l, e, a, n} with length less than 5.
The set of strings over {c, l, e, a, n} with length greater than 7
If you take the union of the regular expressions from the previous two problems, how many strings more does the corresponding set need to contain all of Σ* , where Σ = {c, l, e, a, n}?

engineering Computer-Science

Answer 1

Answer #1

Here (c+l+e+a+n) means if can contain any of the five symbol.

Also (c+l+e+a+n)^2 = (c+l+e-a+n) (c+l+e+a+n) : that means it can contains either of 5 symbol twice which is nothing but string of length 2.

If you have any doubt, please comment down and get it cleared. Just don't simply downvote and leave.

Also if you are satisfied please upvote thanks..

Answer 2

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