8.7 Practice Question

Duration: 2 min

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Module outline

  1. HPSC Interview Preparation: Interview Preparation
  2. Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  3. Data Structure & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Sorting Algorithms, Minimum Spanning Trees, Time Complexity Analysis, Graph Theory, Shortest Path Algos
  4. Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  5. Computer System & Organisation: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer
  6. Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, SQL, File Organization & Indexing, Transaction Management, Concurrency Control
  7. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling
  8. Digital Logic & Circuits: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  9. Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Pushdown Automata & CFG, Turing Machines, Moore & Mealy Machines
  10. 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
  11. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Data Warehousing & Mining
  12. Introduction to Emerging Trends: Emerging Tech Trends, समुच्चय, संबंध, फलन और विविक्त गणित / Sets, Relations, Functions and Discrete Mathematics, व्यापार, विपणन एवं उपभोक्ता संरक्षण / Trade, Marketing and Consumer Protection, कंप्यूटर नेटवर्क / Computer Networks
  13. Digital Society & Cyber Law: Society, Law & Ethics, साइबर सुरक्षा / Cyber Safety and Security
  14. HPSC PGT Previous Year Paper:
  15. HPSC Assistant Professor Previous Year Paper:
  16. Live Sessions: HPSC Live Sessions, EMRS TGT/PGT Live Class
  17. Full Mock Test:
  18. HPSC PGT - MOCK Test Series:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video segment focuses on solving a graph theory practice problem involving simple non-directed graphs. The instructor presents a question asking for the possible number of vertices in a graph with 24 edges where every vertex has an identical degree K. The core concept applied is the Handshaking Lemma, which states that the sum of all vertex degrees equals twice the number of edges. The instructor demonstrates how to translate this theorem into an algebraic equation by defining |V| = x for the number of vertices and deg(v) = K for the degree. Through this derivation, he establishes that x * K must equal 48 (since 24 edges multiplied by 2 equals 48). The solution process involves identifying that the number of vertices x must be a divisor of 48. By testing the provided multiple-choice options (20, 15, 10, and 8), the instructor eliminates values that do not divide 48 evenly. Specifically, he crosses out options a) 20, b) 15, and c) 10 because they are not factors of 48. The remaining option d) 8 is identified as the correct answer since 8 divides 48 to yield an integer degree K of 6. This exercise reinforces the relationship between edges, vertices, and regular graph properties.

Chapters

  1. 0:00 – 1:58 00:00-01:58

    The instructor introduces a graph theory problem displayed on screen asking for the possible number of vertices in a simple non-directed graph with 24 edges where every vertex has degree K. He immediately applies the Handshaking Lemma, writing '24 x 2' to represent twice the number of edges. He assigns variables |V| = x and deg(v) = K to set up the equation x * K = 48. The instructor then systematically evaluates the multiple-choice options a) 20, b) 15, c) 10, and d) 8. He crosses out options a), b), and c) because they are not divisors of 48, leaving d) 8 as the only valid solution where x * K results in an integer degree.

The video provides a concise demonstration of applying the Handshaking Lemma to determine graph properties. The central takeaway is that for a regular graph, the product of vertices and degree must equal twice the number of edges. This creates a divisibility constraint where the vertex count must be a factor of 2E. The instructor's method highlights a practical strategy for multiple-choice questions: calculate the total degree sum (2E), then check which option divides this sum evenly. This approach efficiently filters incorrect answers without needing to construct the actual graph, emphasizing algebraic verification over geometric visualization.

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