Complete Solutions and Summary of Cubes and Cube Roots – NCERT Class 8 Mathematics Chapter 6

Detailed explanations, interesting number patterns, prime factorisation methods, examples, and exercises on cubes, cube roots, and Hardy-Ramanujan numbers from NCERT Class 8 Mathematics Chapter 6.

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Categories: NCERT, Class 8, Mathematics, Number Theory, Cubes and Cube Roots, Chapter 6
Tags: Cubes, Cube Roots, Hardy-Ramanujan Number, Perfect Cubes, Prime Factorisation, NCERT Class 8, Mathematics, Chapter 6, Exercises, Solutions, Number Patterns
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Cubes and Cube Roots - Complete Study Guide

Cubes and Cube Roots

Chapter 6: Mathematics — Complete Study Guide

Clear concepts, worked examples, summaries & exam-style questions

Chapter Overview

1729 Hardy–Ramanujan Number (sum of two cubes)
1–20 Cubes table (1³ to 20³)
EX Examples: perfect cubes & prime factor method
2 Main methods: prime factorisation & pattern recognition

What you'll learn

Definition & Patterns

What are cubes and cube roots; patterns in cube endings and sums of odd numbers giving cubes.

Prime-factor method

How to test perfect cubes and find cube roots via grouping prime factors in triples.

Smallest multiplier/divisor

How to find the least number to multiply/divide to get a perfect cube (by adjusting prime exponents to multiples of 3).

Applications

Volume-side relationships of cubes and useful numeric identities (e.g., sums of consecutive odd numbers).

Quick context

This chapter introduces cubes (numbers of form \(n^3\)) and cube roots (the inverse operation). You will see examples, interesting numerical patterns (like Hardy–Ramanujan type facts), and techniques to decide if a number is a perfect cube and to compute cube roots using prime factorisation. Practical tasks include finding the least multiplier or divisor to make a number a cube and interpreting relationship between volume and side of cubes.