Test: The Language of a Grammar, Inferences & Ambiguity - Computer Science Engineering (CSE) MCQ

The following are the notions to express Context free grammars:
a) Recursive Inferences
b) Derivations
c) Sentential form
d) Parse trees

We apply the productions of CFG to infer that certain strings are in the language of a certain variable.

Two inference approaches:
1. Recursive inference, using productions from body to head
2. Derivations, using productions from head to body

Parse trees are an alternative representation to derivations and recursive inferences. There can be several parse trees for the same string.

Yes, they are equivalent. Both the terminologies represent the two approaches of recursive inferencing.

 A->aA=>aaA=>aab

For the given expression, L(G)={w in T*|S→*w}, If G(V, T, P, S) is a CFG, the language of G, denoted by L(G), is the set of terminal strings that have derivations from the start symbol.

Push down automata accepts context free language.

Using the recursive approach, we can conclude that option a is the correct answer, and its not possible for a grammar to have more than one language.

 Both the statements are false. Recursive Inference, using productions from body to head. Derivations, using productions from head to body.