Practice Question
Duration: 2 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About the Course: About the Course
- Paper-1 & 2 | Basic Numeracy: Ratio and Proportion (Ratios), Divisibility Rules, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Percentage, Average, Mensuration and Geometry, Age Problems, Arithmetic, Statistics, Probability, Profit and Loss, Simple Interest and Compound Interest, Partnership, Speed Mathematics and Basic Mathematics, Algebra, Powers and Exponents (Surds and Indices), Time and Work, Pipe and Cistern, RSSB Specific Videos - Basic Numeracy
- Paper-1 & 2 | Data Interpretation: Data Interpretation
- Paper-1 & 2 | General Mental Ability: Mental Ability, RSSB Specific Videos - Mental Ability
- Paper-1 & 2 | Logical Reasoning and Analytical Ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Syllogisms, Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Venn Diagram, Analogy, Ranking, Order and Sequence, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Data Arrangement, Logical Sequence Of Words, Crypt Arithmetic
- Paper-1 & 2 | Decision Making and Problem Solving: Selection Decision Table (Decision Making)
- Paper-1 | General Science: Physics, Biology, Chemistry, RSSB Specific Videos
- Paper-1 | General Awareness: State Wise GK, GK- Current Affairs
- Paper-2 | Fundamentals of Computer: Basics of COA, Number System, Floating Point Rep, Number Representation
- Paper - 2 | Digital Logic Systems: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits
- Paper-2 | Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Linux OS, Distributed Systems
- Paper-2 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, Relational Calculus, File Organization & Indexing, Transaction Management, Concurrency Control
- Paper-2 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
- Paper-2 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
- Paper 2 | Oops, C++, Java: Language Design, OOPS with C++, Java, .Net Programming, Java Fundamentals
- Paper 2 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
- Paper 2 | Emerging Trends and AI: Emerging Tech Trends, Artificial Intelligence
- Paper-2 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Advanced Algorithms
- Paper 2 | Data Communication and Network Security: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, 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, Ethical Hacking
- Paper-2 I Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- Paper-2 | Computer Organization and Architecture: Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations
- Paper-2 | Web Development: JavaScript-Basics, HTML Basics, CSS, XML
- Pedagogy: Child Development, Concept of Pedagogy, Psychology, Theories, Inclusive Education, Experiential Pedagogy, Curriculum Framework & Reforms, National Education Policy (NEP) 2020
- Live Sessions: RSSB Live Sessions
- RSSB Paper 1 - Full Mock Tests:
- RSSB Paper 2 - Full Mock Tests:
- SCI Previous Year Papers:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video presents a digital logic problem involving a circuit with three 2:1 multiplexers in a specific configuration. The instructor analyzes the circuit to determine the boolean function f. He begins by writing the standard multiplexer equation Y = S0' I0 + S0 I1 below each block. He derives the output of the first MUX, which has inputs 1 and 0 with select line x1, resulting in x1'. He continues for subsequent MUXes, tracing connections and substituting values. The final derivation involves simplifying a complex boolean expression. After working through the logic, he identifies the correct option, circling option (C) which corresponds to the XNOR function f = x1 x2 + x1' x2'.
Chapters
0:00 – 2:00 00:00-02:00
The instructor introduces the circuit diagram, featuring three 2:1 multiplexers in a cascade. He writes the general MUX equation Y = S0' I0 + S0 I1 three times. He starts with the leftmost MUX, noting inputs 1 and 0 and select line x1, writing x1' . 1 + x1 . 0 = x1'. He moves to the middle MUX, where the select line is x2. He writes an expression x2' . x1 + x2 . x1' below it. Finally, he analyzes the rightmost MUX with select line x1, writing a combined expression x1' (x2' x1 + x2 x1') + x1 x2. He simplifies this expression on the board, arriving at a final boolean function. Throughout, he carefully points to connections on the diagram to justify steps.
2:00 – 2:03 02:00-02:03
The video concludes with the instructor finalizing his analysis. The board shows the simplified expression and multiple-choice options. He circles option (C) f = x1 x2 + x1' x2', indicating it as the correct answer. The final frame shows the completed derivation and selected option, confirming the XNOR function as the result of the circuit analysis.
This lecture segment focuses on systematic analysis of digital logic circuits using multiplexers. The instructor demonstrates breaking down a complex circuit into manageable stages by applying the fundamental MUX selection equation. By tracing signal flow from inputs through each stage, he derives the overall boolean function. The example serves as a practical application of boolean algebra and logic circuit design principles, showing how cascaded components implement specific logic functions like XNOR. The visual derivation clearly helps students follow logical steps.