(2) (Ø* u b) b* Ob о bb* О Бь
Database System Concepts
7th Edition
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Chapter1: Introduction
Section: Chapter Questions
Problem 1PE
Related questions
Question
Expert Solution
Step 1: (Ø* U b) b*:
The correct choice is: b*
Break down the given regular expression:
(Ø* U b) b*
Here, Ø represents the empty set, and Ø* represents the set containing only the empty string ε.
The expression (Ø* U b) represents either the empty string ε or the string "b".
Now, b* represents zero or more occurrences of "b".
Thus, when you combine (Ø* U b) with b*, it can represent:
- ε followed by zero or more "b"s - This gives "b*", because ε doesn't add any characters.
- "b" followed by zero or more "b"s - This can give a single "b", "bb", "bbb", etc.
Given the options:
a) b*
b) bb*
c) b*b
Let's evaluate them:
a) b*
- This option matches the first case of our breakdown (ε followed by zero or more "b"s). It also matches the second case because "b" followed by zero "b"s is still "b", and "b" followed by one "b" is "bb", and so on. So, this option is correct.
b) bb*
- This option specifically means one "b" followed by zero or more "b"s. It represents strings like "b", "bb", "bbb", etc. While it represents a subset of the strings represented by (Ø* U b) b*, it doesn't cover all possibilities (it doesn't represent ε followed by zero b's, which is just ε). Therefore, this option is incorrect as a complete representation.
c) b*b
- This option means zero or more "b"s followed by one "b". It represents strings like "b", "bb", "bbb", etc. However, it doesn't represent the empty string ε, which is part of the strings represented by (Ø* U b) b*. So, this option is also incorrect as a complete representation.
Thus, the correct choice is:
a) b*
Step by step
Solved in 3 steps
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.Recommended textbooks for you
Database System Concepts
Computer Science
ISBN:
9780078022159
Author:
Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:
McGraw-Hill Education
Starting Out with Python (4th Edition)
Computer Science
ISBN:
9780134444321
Author:
Tony Gaddis
Publisher:
PEARSON
Digital Fundamentals (11th Edition)
Computer Science
ISBN:
9780132737968
Author:
Thomas L. Floyd
Publisher:
PEARSON
Database System Concepts
Computer Science
ISBN:
9780078022159
Author:
Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:
McGraw-Hill Education
Starting Out with Python (4th Edition)
Computer Science
ISBN:
9780134444321
Author:
Tony Gaddis
Publisher:
PEARSON
Digital Fundamentals (11th Edition)
Computer Science
ISBN:
9780132737968
Author:
Thomas L. Floyd
Publisher:
PEARSON
C How to Program (8th Edition)
Computer Science
ISBN:
9780133976892
Author:
Paul J. Deitel, Harvey Deitel
Publisher:
PEARSON
Database Systems: Design, Implementation, & Manag…
Computer Science
ISBN:
9781337627900
Author:
Carlos Coronel, Steven Morris
Publisher:
Cengage Learning
Programmable Logic Controllers
Computer Science
ISBN:
9780073373843
Author:
Frank D. Petruzella
Publisher:
McGraw-Hill Education