9.2 Practice Question

Duration: 3 min

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Inside: a video lesson and guided study material.

Module outline

  1. About Course: UPPSC Course Overview
  2. Interview Preparation & Guidance: Interview Preparation
  3. Paper 1 | General Hindi: हिन्दी की रूप रचना, वर्णमाला, समास, बहु-विषयक सामग्री (विभिन्न अवधारणाओं को जोड़ने वाली सामग्री), हिन्दी की ध्वनि और स्वनिम व्यवस्था, प्राचीन और मध्यकालीन भारतीय आर्यभाषाएँ, काव्य के लक्षण, हेतु और प्रयोजन, हिन्दी शब्द रचना, हिन्दी साहित्येतिहास दर्शन, भक्तिकालीन काव्यधाराएँ, भारतीय काव्यशास्त्र की परंपरा, भारतीय नवजागरण और स्वाधीनता आंदोलन, अन्य गद्य विधाएँ एवं प्रवासी साहित्य, निर्धारित उपन्यासों का तुलनात्मक अध्ययन, गोदान, हिन्दी कहानी का विकास, स्वातंत्र्योत्तर और नयी कहानी, हिन्दी निबंध का विकास, शुक्लोत्तर निबंध, द्विवेदी और शुक्ल युग के निबंध, हिन्दी की संवैधानिक स्थिति, आधुनिक भारतीय आर्यभाषाएँ और हिन्दी का उद्भव, हिन्दी भाषा प्रयोग के विविध रूप, रीतिकाल, जीवनी, द्विवेदी युग और छायावाद, रीति, वक्रोक्ति और औचित्य सिद्धान्त, शब्दशक्ति और ध्वनि सिद्धान्त, रस सिद्धान्त और साधारणीकरण, उत्तर आधुनिकतावाद, लोहिया दर्शन, हिन्दी उपन्यास का विकास, हिन्दी नवजागरण, अंबेडकर दर्शन, आदिकाल, प्रयोगवाद और नयी कविता, छायावादी काव्य: प्रसाद और निराला, प्रगतिवाद से समकालीन कविता, निर्गुण भक्ति काव्य, द्विवेदीयुगीन काव्य, रीतिकालीन काव्य, आरंभिक हिन्दी उपन्यास, स्वातंत्र्योत्तर उपन्यास, आत्मकथा, स्वाधीनता-पूर्व प्रेमचंदोत्तर उपन्यास, निर्धारित कहानियों का तुलनात्मक अध्ययन, साठोत्तरी नाटक, प्रसाद और प्रसादोत्तर युग के नाटक, भारतेन्दु युगीन नाटक, स्वातंत्र्योत्तर नाटक, भारतेन्दु युगीन निबंध, संस्मरण और रेखाचित्र, व्यंग्य, एक साहित्यिक की डायरी, संस्कृति के चार अध्याय, सगुण भक्ति काव्य, हिन्दी नाटक, एकांकी और रंगमंच, आधुनिक गद्य और हिन्दी नवजागरण, अलंकार सिद्धान्त, हिन्दी आलोचना का विकास, भक्ति आंदोलन, कल्पना, बिम्ब, प्रतीक, मिथक और फंतासी, नयी कविता का विस्तार और साठोत्तरी कविता, उत्तर-छायावादी और प्रगतिवादी काव्य, काव्यगुण और काव्यदोष, प्लेटो, अरस्तू और पाश्चात्य परंपरा, मार्क्सवाद, स्वच्छन्दतावादी काव्यशास्त्र, आधुनिक पाश्चात्य आलोचना, भाषा और भाषा परिवार, देवनागरी लिपि
  4. Paper 2 | General Studies: State Wise GK / राज्यवार सामान्य ज्ञान (GK), Polity / राजव्यवस्था, Geography / भूगोल, History / इतिहास, GK- Current Affairs / GK- समसामयिकी
  5. Paper 1 | Programming Language: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++
  6. Paper 1 | Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, ORDBMS, NoSQL
  7. Paper 1 | Cyber Security: Computer Fundamentals and Hardware, Literal Comprehension, Computer Software, Inferential Comprehension, Critical Comprehension, Internet and World Wide Web, Email and Online Communication, Cyber Security, Waste Management / अपशिष्ट प्रबंधन, Digital Ethics, IPR and Society, Digital and New Media / डिजिटल एवं नव माध्यम, Research Ethics / शोध नैतिकता, Emerging Technologies, ICT in Education and Governance, Society, Law & Ethics, Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Electronic Data Interchange and E-Commerce, Physical Security and Cryptography Basics, Intrusion Detection Systems (IDS), Cyber Safety and Security, Ethical Hacking, Protection of Geographical Indications / भौगोलिक संकेतों का संरक्षण
  8. Paper 1 | Computer Organization and Architecture: Basics of COA, Programming the Basic Computer, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design
  9. Paper 1 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  10. Paper 1 | Design and Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  11. Paper 1 | Data Structures: Introduction to DS, Array, Linked List, Stack, Queue, Tree, Graphs, Hashing
  12. Paper 1 | Discrete Structures and Theory of Logic: Permutation, Combination and Probability / क्रमचय, संचय एवं प्रायिकता, Set Theory, Relations, Functions, Propositional and Predicate Logic, Graph Theory, Group Theory
  13. Paper 1 | Software Project Management: Software Project Management
  14. Paper 2 | Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Security
  15. Paper 2 | Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment, Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Pushdown Automata & CFG, Complexity Theory
  16. Paper 2 | Artificial Intelligence & High Performance Computing: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Planning, Multi Agent Systems, Natural Language Processing, Cloud and Distributed Computing
  17. Paper 2 | Image Processing: Digital Image Fundamentals, Image Enhancement, Image Restoration, Color Image Processing, Image Compression
  18. Paper 2 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  19. Paper 2 | Computer Graphics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing
  20. Paper 2 | Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, HTML Basics, JavaScript-Basics, Java
  21. Paper 2 | Soft Computing: Fuzzy Sets, Artificial Neural Networks, Genetic Algorithms
  22. Paper 2 | Distributed System: Distributed Systems
  23. UPPSC Live Class Recordings: UPPSC Polytechnic Lecturer 2025 (CS)
  24. Previous Year Papers:
  25. Mock Test:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video segment presents a practice problem in set theory focusing on the cardinality of nested power sets. The instructor addresses the question: If φ is an empty set, what is |P(P(P(φ)))|? The lesson begins by introducing the problem statement on screen, offering multiple-choice options. To clarify the concept of power sets before tackling the empty set directly, the instructor first defines a concrete example using a non-empty set A = {a}. This pedagogical strategy helps visualize how power sets are constructed. The instructor writes out P(A) = {φ, {a}} and then expands it to P(P(A)), listing all subsets explicitly. This step-by-step expansion demonstrates the recursive nature of power sets, showing how each element becomes a subset in the next iteration. The instructor then transitions to applying this logic to the empty set φ, calculating P(φ) = {φ}, followed by P(P(φ)) and finally the target expression. The solution relies on the cardinality formula 2^n, where n is the number of elements in a set. By calculating successive powers of two (2^0, 2^1, 2^2), the instructor derives the final answer of 4.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with the instructor presenting a set theory practice question displayed on screen: 'If φ is an empty set. Then |P(P(P(φ)))| =______?' with options a) 1, b) 2, c) 4, d) none of above. The instructor begins the solution process by introducing a concrete example to illustrate power set construction, writing 'A = {a}' on the board. He then defines the power set of A as 'P(A) = {φ, {a}}', explicitly showing that the power set contains both the empty set and the original element. This initial phase establishes the foundational concept of a power set before moving to the more complex nested structure required by the main problem. The instructor's method of starting with a simple non-empty set serves as a scaffold for understanding the subsequent recursive application to the empty set.

  2. 2:00 – 2:45 02:00-02:45

    In the final segment, the instructor applies the previously demonstrated logic to solve for the cardinality of nested power sets of the empty set. He writes 'P(φ) = {φ}' to show that the power set of an empty set contains one element (the empty set itself). He then calculates 'P(P(φ)) = {φ, {φ}}', demonstrating that the cardinality doubles to 2. Finally, he expands this to 'P(P(P(φ))) = {φ, {φ}, {{φ}}, {φ, {φ}}}', listing the four distinct elements. The instructor explicitly writes '2^0 = 1', '2^1 = 2', and '2^2 = 4' to highlight the exponential growth pattern. The video concludes with the selection of option (c) as the correct answer, confirming that |P(P(P(φ)))| equals 4.

The lecture effectively bridges abstract set theory concepts with concrete calculation methods. The core pedagogical technique involves using a non-empty example (A={a}) to demystify the definition of power sets before applying it to the counter-intuitive case of the empty set. The instructor emphasizes that P(φ) is not empty but contains one element, φ itself. This distinction is crucial for correctly calculating nested power sets. The progression from P(φ) to P(P(φ)) to P(P(P(φ))) illustrates the recursive definition where each step doubles the cardinality. The final answer of 4 is derived through direct enumeration and confirmed by the formula 2^n, where n represents the cardinality of the previous set. This approach reinforces both the definition-based and formula-based methods for solving such problems.

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