Integer Class 9 Notes | EduRev

Class 9 : Integer Class 9 Notes | EduRev

The document Integer Class 9 Notes | EduRev is a part of Class 9 category.
All you need of Class 9 at this link: Class 9

All the integers are
  • a)
    whole numbers
  • b)
    rational numbers
  • c)
    irrational numbers
  • d)
    natural numbers
Correct answer is option 'B'. Can you explain this answer?

Ref: https://edurev.in/question/501991/All-the-integers-area-whole-numbersb-rational-numb

An integer (pronounced IN-tuh-jer) is a whole number (not a fractional number) that can be positive, negative, or zero.

Examples of integers are: -5, 1, 5, 8, 97, and 3,043.

Examples of numbers that are not integers are: -1.43, 1 3/4, 3.14, .09, and 5,643.1.

The set of integers, denoted Z, is formally defined as follows:

Z = {..., -3, -2, -1, 0, 1, 2, 3, ...}

In mathematical equations, unknown or unspecified integers are represented by lowercase, italicized letters from the "late middle" of the alphabet. The most common are p, q, r, and s.



The set Z is a denumerable set. Denumerability refers to the fact that, even though there might be an infinite number of elements in a set, those elements can be denoted by a list that implies the identity of every element in the set. For example, it is intuitive from the list {..., -3, -2, -1, 0, 1, 2, 3, ...} that 356,804,251 and -67,332 are integers, but 356,804,251.5, -67,332.89, -4/3, and 0.232323 ... are not.

The elements of Z can be paired off one-to-one with the elements of N, the set of natural numbers, with no elements being left out of either set. Let N = {1, 2, 3, ...}. Then the pairing can proceed in this way:

Integer Class 9 Notes | EduRev

In infinite sets, the existence of a one-to-one correspondence is the litmus test for determining cardinality, or size. The set of natural numbers and the set of rational numbers have the same cardinality as Z. However, the sets of real numbers, imaginary numbers, and complex numbers have cardinality larger than that of Z.

Offer running on EduRev: Apply code STAYHOME200 to get INR 200 off on our premium plan EduRev Infinity!

Related Searches

Integer Class 9 Notes | EduRev

,

Exam

,

video lectures

,

mock tests for examination

,

Integer Class 9 Notes | EduRev

,

Semester Notes

,

Free

,

ppt

,

practice quizzes

,

MCQs

,

Previous Year Questions with Solutions

,

Extra Questions

,

Sample Paper

,

Integer Class 9 Notes | EduRev

,

Objective type Questions

,

study material

,

Summary

,

Viva Questions

,

pdf

,

past year papers

,

shortcuts and tricks

,

Important questions

;