Series with combination

Duration: 12 min

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Module outline

  1. About Course: About the Course
  2. Paper 2 | Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
  3. Paper 2 | Computer Organization And Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Control Unit Design, Instr Formats & Modes, Programming the Basic Computer
  4. Paper 2 | Analog And Digital Communication: Introduction to Communication Systems & Random Signals, Analog Communication Systems, Information Theory & Digital Communication Fundamentals, Digital Modulation & Detection Techniques, Error Control, Synchronization & Multiple Access Techniques
  5. Paper 2 | Programming in C: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  6. Paper 2 | Data Structures And Programming: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Java, OOPS with C++, Java Fundamentals, Array, String, IO & References
  7. Paper 2 | Algorithms: Algorithm Analysis, Sorting Algorithms, Time Complexity Analysis, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  8. 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
  9. Paper 2 | Operating System: 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
  10. Paper 2 | Databases: 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
  11. Paper 2 | Information Systems and Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  12. Paper 2 | 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
  13. Paper 2 | Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, HTML Basics, JavaScript-Basics, CSS, XML, HTML5
  14. Paper 2 | Cyber Security And Emerging Technologies: Emerging Tech Trends, Internet of Things
  15. Paper 2 | Cloud Technology: Cloud Computing
  16. Paper 2 | Probability and statistics: Probability, Statistics
  17. Paper-1 English: Vocabulary, Preposition, Articles, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Cloze Test (Cloze Passage), Sentence Construction
  18. Paper 1 General Mental Ability & Logical reasoning: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Percentage, Average, Powers and Exponents (Surds and Indices), Algebra, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Mensuration and Geometry, Mental Ability, Age Problems, Partnership, Arithmetic, Speed Mathematics and Basic Mathematics, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Venn Diagram, Analogy
  19. Paper-1 General Knowledge & Current Affairs: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge
  20. Full Length Mock Test:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture introduces number and letter series, focusing on a difference-based trick for solving sequences. It presents three example series: 2, 5, 10, 17, 26, 37; 2, 6, 12, 20, 30, 42; and 0, 2, 6, 12, 20, 30. The instructor calculates first differences (e.g., +3, +5, +7 for the first series) and second differences to identify patterns. A key rule '±1 ±n' is highlighted, relating terms to index positions and base powers. The lesson then transitions to combination patterns like n²+1, n³-1, and cube-square combinations. A worked example shows 2, 5, 10, 17, 26, 37 as n²+1 (base squares 1,4,9,16,25,36 plus constant 1), yielding next term 7²+1=50. Another example works out 2, 9, 28, 65, 126 using cube gaps (1,8,27,64) with next value 125. The video concludes with a 'Series with Combination' slide listing ten patterns from Square+1 to Cube-Square, ending with 'THANKS FOR WATCHING'.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card 'NUMBER SERIES - LETTER SERIES' displaying the alphabet and digits, then transitions to a slide titled 'An Important Trick'. Three number series are presented: 2, 5, 10, 17, 26, 37; 2, 6, 12, 20, 30, 42; and 0, 2, 6, 12, 20, 30. A red check mark appears under the leading '2' of the middle series, followed by red difference values 4, 6, 8, 10, 12, 14 written beneath it with connecting check marks. The value '56' is handwritten in red into the middle series blank, and partial differences 2, 4, 6, 8 appear under the bottom series.

  2. 2:00 – 5:00 02:00-05:00

    The instructor demonstrates the difference method across all three series. For the first series, differences 3, 5, 7, 9, 11, 13 are written; for the second, 4, 6, 8, 10, 12; for the third, 2, 4, 6, 8, 10. A boxed rule '±1 ±n' is highlighted to guide pattern recognition. Index numbers 1, 2, 3, 4, 5, 6 are written below the first series, and a formula involving '±n' is applied to relate terms to their positions. Second-order differences of 2, 2, 2, 2 are calculated for both the first and third series, confirming constant second differences.

  3. 5:00 – 10:00 05:00-10:00

    The lesson shifts to combination patterns. Formulas such as n²+1, n³-1, and cube+square are listed. The series 2, 5, 10, 17, 26, 37 is broken into base squares (1, 4, 9, 16, 25, 36) with a constant +1 added to each, yielding the next term as 7²+1=50. The slide 'Series with Combination' lists ten patterns from 'Square + 1' to 'Cube - Square' alongside formulas like n²+1, n³-n, and n³-n². Red handwriting works out the series 2, 9, 28, 65, 126 with gaps 1, 8, 27, 64 and a next value 125.

  4. 10:00 – 12:09 10:00-12:09

    The final segment revisits the 'An Important Trick' slide, showing 2, 5, 10, 17, 26, 37 annotated in red with square-based differences and the form 'n² + (n)'. A drawing tool palette is visible on the left. The 'Series with Combination' slide reappears, listing ten patterns and formulas. A second row 0, 4, 18, 48, 106 is worked out alongside the cube-gap example. The video concludes with 'THANKS FOR WATCHING' on screen.

The lecture teaches a systematic approach to number series using first and second differences, then extends to combination patterns involving squares and cubes. The core method: compute consecutive differences; if first differences form an arithmetic progression (odd or even numbers), the second difference is constant. The '±1 ±n' rule connects terms to index positions, enabling formula-based solutions like n²+1. Worked examples demonstrate both the difference method (yielding 56 for the middle series) and the combination approach (yielding 50 for n²+1 and 125 for cube-gap series). The ten-pattern reference list provides a quick lookup for common combination types.

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