8.3 Practice Question

Duration: 3 min

This video lesson is available to enrolled students.

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Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. CS | 01 | Digital Logic and Circuits and Discrete Mathematical Structures: Digital Systems & Boolean Basics, Number System, Number Representation, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Permutation and Combination / क्रमचय और संचय
  3. CS | 02 | Computer Organization and Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Multiprocessors
  4. CS | 03 | Data Structures and Algorithm: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Complexity Theory, Advanced Algorithms
  5. CS | 04 | Problem Solving through C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  6. CS | 05 | Object Oriented Techniques: Object Oriented Technology, Java
  7. CS | 06 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Unix OS
  8. CS | 07 | Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization, Query Processing & Optimization, File Organization & Indexing
  9. CS | 08 | 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
  10. CS | 09 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  11. CS | 10 | Internet Technology, Web Design and Web Technology: Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, JavaScript-Basics, HTML Basics
  12. CS | 11 | System Analysis And Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Security, Risk Management & Maintenance
  13. CS | 12 | Information Security and Cyber Laws: 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
  14. CS | 13 | Computer Graphics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing
  15. GS Paper | 01 | Indian and World Geography / भारत एवं विश्व का भूगोल: Geography / भूगोल
  16. GS Paper | 02 | History / इतिहास: History / इतिहास
  17. GS Paper | 03 | Indian Economy & Social Development / भारतीय अर्थव्यवस्था एवं सामाजिक विकास: Indian Economy / भारतीय अर्थव्यवस्था
  18. GS Paper | 04 | General Science / सामान्य विज्ञान: Biology / जीव विज्ञान, Chemistry / रसायन विज्ञान, Scientific Achievements and Research / वैज्ञानिक उपलब्धियाँ और अनुसंधान
  19. GS Paper | 05 | Elementary Maths / प्रारंभिक गणित: Number System / संख्या पद्धति, Divisibility Rules / विभाज्यता के नियम, HCF and LCM / महत्तम समापवर्तक और लघुत्तम समापवर्त्य, Percentage / प्रतिशत, Profit, Loss and Discount / लाभ, हानि और बट्टा, Simple and Compound Interest / साधारण और चक्रवृद्धि ब्याज, Ratio and Proportion / अनुपात और समानुपात, Average / औसत, Time and Work / समय और कार्य, Time, Speed and Distance / समय, चाल और दूरी, Algebra / बीजगणित, Solid Mensuration / घन क्षेत्रमिति, Data Interpretation / आँकड़ा निर्वचन, Arithmetic / अंकगणित, Statistics / सांख्यिकी, Probability / प्रायिकता, Sequences, Series and Combinatorics / अनुक्रम, श्रेणी और संयोजन, Mixture and Alligation / मिश्रण और एलिगेशन, Calculus / कलन, Trigonometry / त्रिकोणमिति, Vectors / सदिश, Number Systems and Number Theory / संख्या पद्धति और संख्या सिद्धांत, Euclidean Geometry and Mensuration / यूक्लिडीय ज्यामिति और क्षेत्रमिति, Statistics and Probability / सांख्यिकी और प्रायिकता, Coordinate Geometry, Vectors and 3D Geometry / निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति, Polynomials, Equations and Complex Numbers / बहुपद, समीकरण और सम्मिश्र संख्याएँ, Plane Mensuration / समतल क्षेत्रमिति, Simplification, Indices and Surds / सरलीकरण, घातांक और करणी, Sets, Relations, Functions and Discrete Mathematics / समुच्चय, संबंध, फलन और विविक्त गणित
  20. GS Paper | 06 | Indian Polity and Governance / भारतीय राजव्यवस्था एवं शासन: Polity / राजव्यवस्था
  21. GS Paper | 07 | Current Events / समसामयिक घटनाएँ: Current Affairs / समसामयिकी
  22. UPLT Live Classes Notes: UPLT Live Classes
  23. UPLT Full Mock Tests Tier 1:
  24. UPLT Full Mock Tests Tier 2:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video segment demonstrates the application of the Handshaking Lemma in graph theory to solve for an unknown number of vertices. The problem presented involves a simple graph G with 21 edges, where three vertices have a degree of 4 and all remaining vertices have a degree of 2. The instructor systematically applies the fundamental theorem stating that the sum of vertex degrees equals twice the number of edges. By defining the total number of vertices as x, the remaining vertices are expressed as (x-3). The solution process involves setting up a linear equation based on the degree sum, substituting known values, and performing algebraic simplification to isolate x. The final calculation reveals that the graph contains exactly 18 vertices.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video begins with the instructor presenting a graph theory problem displayed on screen: 'A simple graph G contains 21 edges, 3 vertices of degree 4 and all the remaining vertices are of degree 2.' The instructor writes down the Handshaking Lemma formula, explicitly stating that the sum of degrees from i=1 to n equals deg(vi). Key teaching cues include identifying the given values of 21 edges and distinguishing between vertices of degree 4 versus those of degree 2. The instructor underlines key terms in the question to emphasize constraints and sets up the foundational equation required for solving the unknown variable representing total vertices.

  2. 2:00 – 2:41 02:00-02:41

    In the final segment, the instructor executes the algebraic solution derived from the Handshaking Lemma. The visible equation on screen shows 3x4 + (x-3)x2 = 21x2, representing the sum of degrees equating to twice the edge count. The instructor simplifies this expression step-by-step, showing 12 + 2x - 6 = 42. Through algebraic manipulation, the variable x is isolated to find its value. The instructor circles the final answer of 18, confirming that the graph contains 18 vertices total. This section concludes the problem-solving demonstration by verifying the calculation and presenting the definitive result.

The core educational value of this video lies in demonstrating the practical application of the Handshaking Lemma, a fundamental concept in graph theory. The problem serves as a concrete example of how abstract mathematical theorems translate into solvable algebraic equations. By breaking down the problem into identifying knowns (edges and specific vertex degrees) and unknowns (total vertices), the instructor models a systematic approach to graph problems. The transition from theoretical formula to numerical solution highlights the importance of algebraic skills in discrete mathematics. Students should note that defining variables clearly, such as letting x represent total vertices and (x-3) represent remaining vertices, is crucial for setting up correct equations. The final answer of 18 validates the method and reinforces the relationship between edge counts and vertex degrees.

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