NullEmpty Set and Universal Set
Duration: 5 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
- General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
- Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
- Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
- Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
- Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
- Databases: 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, Database Recovery, Database Security & Authorization
- Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
- Theory of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
- 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
- Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
- Computer Networks: Introduction to CN, 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, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
- Full Length Mock Tests:
- Sectional Tests:
- Paper 2 - Full-length Mock Tests:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video provides a foundational lecture on set theory, specifically focusing on two critical types of sets: the Null (or Empty) set and the Universal set. The instructor, Sanchit Jain Sir, utilizes a combination of text slides and handwritten board examples to clarify definitions, notations, and visual representations. The session begins by defining the Null set as the unique set containing no elements, establishing its cardinality as zero. It then transitions to the Universal set, defining it as the fixed set containing all objects under investigation, typically represented by a rectangle in Venn diagrams. The lecture emphasizes the importance of precise notation, distinguishing between an empty set and a set containing an empty set, and visually demonstrates how subsets relate to the universal set.
Chapters
0:00 – 2:00 00:00-02:00
The segment introduces the concept of the Null set or empty set. The on-screen text defines it as the unique set having no elements, with a cardinality of zero, denoted mathematically as $|\phi| = 0$. The slide notes that it is denoted by the symbol $\phi$ or $\{\}$. The instructor writes examples on the whiteboard, starting with a set $A = \{1, 2, 3\}$ to contrast with an empty set $A = \{\}$. He explicitly writes $\{\} = \phi$ to show equivalence. Crucially, he writes $\{\phi\}$ and crosses it out, explaining that a set containing the symbol $\phi$ is not a null set but a singleton set, as it has one element. This distinction is highlighted as a common point of confusion.
2:00 – 5:00 02:00-05:00
The lecture shifts to the definition of a Universal set. The slide text explains that if all sets under investigation are subsets of a fixed set, that fixed set is the Universal set. It contains all objects under investigation and is denoted by the symbol $U$. In Venn diagrams, it is represented by a rectangle. The instructor draws a large rectangle on the board labeled $U$ to visualize this concept. Inside this rectangle, he draws several circles to represent different subsets, illustrating that all these subsets exist within the boundaries of the universal set. This visual aid reinforces the text definition that the universal set encompasses everything relevant to the current mathematical context.
5:00 – 5:26 05:00-05:26
The final segment concludes the explanation of the Universal set. The instructor continues to reference the drawn rectangle labeled $U$ on the board. He reiterates that in Venn diagrams, the universal set is represented by a rectangle, enclosing all other sets being discussed. The slide text remains visible, reinforcing the definition that it is the set containing all objects under investigation. The instructor ensures students understand that the universal set is context-dependent, serving as the fixed container for all subsets in a specific problem or investigation.
The video effectively bridges theoretical definitions with practical examples. It starts with the Null set, clarifying that having no elements means cardinality is zero, and warns against confusing the empty set with a set containing the empty set symbol. It then moves to the Universal set, establishing it as the overarching container for all sets in a given context. The use of Venn diagrams (rectangles for universal, circles for subsets) provides a visual framework for understanding set relationships. The progression from specific definitions to visual representation helps solidify the concepts for students.

