, COS2601-26-Y Assessments Assessment 1
QUIZ
Question 1 What is the difference between the Kleene star (Σ*) and the positive closure (Σ+)?
Answer saved
Marked out of Σ+ includes the empty string, while Σ* does not.
1.00
Σ+ and Σ* are the same.
Σ* includes the empty string, while Σ+ does not.
Σ+ contains only strings of even length.
Clear my choice
Question 2 Which of the following best describes a formal language in the set-theoretic definition?
Not yet
answered
A sequence of rules used to derive strings.
Marked out of
1.00 A subset of all possible strings over a given alphabet.
A machine that accepts or rejects input strings.
A collection of non-terminal and terminal symbols.
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Question 3 If L = {a b}, what is L*?
Answer saved
Marked out of {a b ab ba aabb...}
1.00
{∧ a b}
{an bm | n, m ≥ 1}
{∧ a b aa ab ba bb aaa aab...}
Clear my choice
QUIZ
Question 1 What is the difference between the Kleene star (Σ*) and the positive closure (Σ+)?
Answer saved
Marked out of Σ+ includes the empty string, while Σ* does not.
1.00
Σ+ and Σ* are the same.
Σ* includes the empty string, while Σ+ does not.
Σ+ contains only strings of even length.
Clear my choice
Question 2 Which of the following best describes a formal language in the set-theoretic definition?
Not yet
answered
A sequence of rules used to derive strings.
Marked out of
1.00 A subset of all possible strings over a given alphabet.
A machine that accepts or rejects input strings.
A collection of non-terminal and terminal symbols.
Clear my choice
Question 3 If L = {a b}, what is L*?
Answer saved
Marked out of {a b ab ba aabb...}
1.00
{∧ a b}
{an bm | n, m ≥ 1}
{∧ a b aa ab ba bb aaa aab...}
Clear my choice
