Question

Regular Expression R and the language it describes can be represented as:

(a) R, R(L)

(b) L(R), R(L)

(c) R, L(R)

(d) All of the mentioned

I have been asked this question in class test.

Origin of the question is Building Regular Expressions topic in chapter Regular Expressions and Languages of Automata Theory

Answer 1

Right option is (c) R, L(R)

The best explanation: When we wish to distinguish between a regular expression R and the language it represents; we write L(R) to be the language of R.