Day 06Part 10 – Operating System for gate-Examples based on multiplicative and additive modulo

Day 06Part 10 – Operating System for gate-Examples based on multiplicative and additive modulo

https://www.gyanodhan.com/video/7B7.%20GATE%20CSEIT/Operating%20System/384.%20Day%2006Part%2010%20-%20Operating%20System%20for%20gate-Examples%20based%20on%20multiplicative%20and%20additive%20modulo.mp4

It looks like you’re looking for Operating System (OS) concepts related to modulo operations for GATE preparation. However, multiplicative and additive modulo are more commonly associated with Discrete Mathematics and Number Theory rather than Operating Systems.

Could you clarify whether you’re looking for:

1. Modulo operations in Discrete Mathematics (e.g., in Cryptography, Hashing, or Number Theory).
2. Modulo operations in Operating Systems (e.g., in Scheduling Algorithms, Page Replacement, or Clock Algorithms).
3. Examples of OS problems related to modulo arithmetic for GATE preparation.

Let me know, and I’ll provide the most relevant material!

Modular arithmetic is a fundamental concept in computer science and plays a significant role in various areas, including operating systems, cryptography, and algorithm design. Understanding modular addition and multiplication is crucial for solving problems related to hashing, memory addressing, and synchronization mechanisms.

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Modular Addition

Definition: In modular addition, the sum of two integers wraps around upon reaching a certain value, known as the modulus. The operation is defined as:GeeksforGeeks

$$(a+b)\mathrm{mod}n$$

Example: Let’s consider modulus $n=7$:

• $(3+5)\mathrm{mod}7=8\mathrm{mod}7=1$

• $(6+4)\mathrm{mod}7=10\mathrm{mod}7=3$Math Sites UNCG

Properties:

• Commutative: $a+b\mathrm{mod}n=b+a\mathrm{mod}n$

• Associative: $(a+b)+c\mathrm{mod}n=a+(b+c)\mathrm{mod}n$GeeksforGeeks

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Modular Multiplication

Definition: Modular multiplication involves multiplying two integers and then taking the modulus:GeeksforGeeks

$$(a\times b)\mathrm{mod}n$$

Example: With modulus $n=7$:

$(3\times 4)\mathrm{mod}7=12\mathrm{mod}7=5$

• $(5\times 6)\mathrm{mod}7=30\mathrm{mod}7=2$Math Sites UNCG

Properties:

• Commutative: $a\times b\mathrm{mod}n=b\times a\mathrm{mod}n$

• Associative: $(a\times b)\times c\mathrm{mod}n=a\times (b\times c)\mathrm{mod}n$

• Distributive over addition: $a\times (b+c)\mathrm{mod}n=(a\times b+a\times c)\mathrm{mod}n$

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Applications in Operating Systems

Modular arithmetic is utilized in various aspects of operating systems:Mathematics LibreTexts

• Hash Functions: Used in hash tables for indexing and quick data retrieval.

• Memory Management: Calculating addresses in circular buffers or ring buffers.

• Process Scheduling: Determining time slices and managing cyclic queues.

• Cryptography: Implementing encryption algorithms that rely on modular operations.

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Practice Problems

1. Problem: Compute $(9+8)\mathrm{mod}7$

   • Solution: $17\mathrm{mod}7=3$Math Sites UNCG

2. Problem: Compute $(4\times 5)\mathrm{mod}7$

   • Solution: $20\mathrm{mod}7=6$Math Sites UNCG

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Further Reading

• Modular Arithmetic – GeeksforGeeks

• Modular Arithmetic – Wikipedia

• Modular Arithmetic – Khan Academy

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Understanding modular arithmetic is essential for tackling various problems in computer science and operating systems. It provides a foundation for designing efficient algorithms and managing system resources effectively.

If you need more examples or have specific questions, feel free to ask!