Regular Expressions

**1.**

The grammar defined by regular expressions is known as?

**2.**

The language defined by regular grammar is known as?

**3.**

Union of two languages L and M is written as?

**4.**

Concatenation (.) has the ________ highest precedence

**5.**

Which of them are not left associative ?

**6.**

The RE in which any number of 0′s is followed by any number of 1′s followed by any number of 2′s is?

**7.**

Which of the following is NOT the set of regular expression R = (ab + abb)* bbab?

**8.**

Consider the production of the grammar S->AA A->aa A->bb Describe the language specified by the production grammar.

**9.**

If R is regular language and Q is any language (regular/ non regular), then Pref (Q in R) is _____________

**10.**

The non terminal that gives null will said to have a null production