Set Theory and Relations Quiz
10 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following sets are related under the relation R defined by |a - b| is even?

  • {1, 3, 5} (correct)
  • {3, 4}
  • {1, 2}
  • {2, 4} (correct)
  • The relation R defined by R = {(L1, L2) : L1 is parallel to L2} is reflexive.

    True

    What is an example of a relation that is symmetric but neither reflexive nor transitive?

    R = {(1, 2), (2, 1)}

    The relation R defined on triangles, where T1 is similar to T2, can be deemed __________.

    <p>an equivalence relation</p> Signup and view all the answers

    Match the type of relation with its properties:

    <p>Reflexive = Every element is related to itself Symmetric = If a is related to b, then b is related to a Transitive = If a is related to b and b is related to c, then a is related to c Antisymmetric = If a is related to b and b to a, then a must equal b</p> Signup and view all the answers

    Which of the following is an example of a relation from the set of students in Class XII to Class XI?

    <p>{(a, b) ∈ A × B: a is sibling of b}</p> Signup and view all the answers

    In mathematics, a relation is always a connection based on a recognisable link.

    <p>False</p> Signup and view all the answers

    What is the range of a relation?

    <p>The range of a relation is the set of all second elements from the ordered pairs in the relation.</p> Signup and view all the answers

    A relation that contains no elements is called the ______.

    <p>empty set</p> Signup and view all the answers

    Match the types of relations with their descriptions:

    <p>Reflexive = Every element is related to itself Symmetric = If a is related to b, then b is related to a Transitive = If a is related to b, and b is related to c, then a is related to c Antisymmetric = If a is related to b and b is related to a, then a must equal b</p> Signup and view all the answers

    Study Notes

    Relation Definitions

    • A relation between sets A and B is a subset of A × B.
    • Empty relation: No element of A is related to any element of A, represented as φ.
    • Universal relation: Each element of A is related to every element of A, represented as A × A.
    • Reflexive relation: Every element 'a' in set A is related to itself, (a, a) ∈ R.
    • Symmetric relation: If element 'a1' is related to 'a2', then 'a2' is related to 'a1', (a1, a2) ∈ R implies (a2, a1) ∈ R.
    • Transitive relation: If 'a1' is related to 'a2' and 'a2' is related to 'a3', then 'a1' is related to 'a3', (a1, a2) ∈ R and (a2, a3) ∈ R implies (a1, a3) ∈ R.
    • Equivalence relation: A relation that is reflexive, symmetric, and transitive.

    Function Definitions

    • A function is a special type of relation where each element in the domain maps to exactly one element in the codomain.
    • One-one (injective) function: Distinct elements in the domain map to distinct elements in the codomain, f(x1) = f(x2) implies x1 = x2.
    • Many-one function: At least two elements in the domain map to the same element in the codomain.
    • Onto (surjective) function: Every element in the codomain is the image of at least one element in the domain, for every y in Y, there exists an x in X such that f(x) = y.
    • Bijective function: A function is both one-one and onto.

    Examples

    • Example 1: In a boys' school, the relation "a is sister of b" is the empty relation, while the relation "the difference between heights of a and b is less than 3 meters" is the universal relation.
    • Example 2: The relation "T1 is congruent to T2" in the set of all triangles is an equivalence relation.
    • Example 7: The relation "f(x) = roll number of student x" in the set of all students of Class X is a one-one and onto function.

    Function Historical Development

    • The concept of function has evolved over time, starting with Descartes who used the word "function" to describe positive powers of a variable.
    • Gregory expanded this to include quantities derived through algebraic operations, while Leibnitz defined functions as quantities depending on variables.
    • John Bernoulli introduced the notation φx for functions, later standardized by Euler.
    • Lagrange discussed analytic functions and used the notation we recognize today, like f(x) and F(x).
    • Dirichlet provided a more rigorous definition of a function which was further refined with the development of set theory.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Relations and Functions PDF

    Description

    Test your understanding of relations and functions in set theory. This quiz covers key concepts such as empty relations, equivalence relations, and different types of functions including injective functions. Ideal for students learning set theory or preparing for exams.

    More Like This

    Types of Relations in Set Theory
    15 questions
    Relations and Functions in Math
    5 questions

    Relations and Functions in Math

    ConciliatoryPythagoras avatar
    ConciliatoryPythagoras
    BCA Math Unit 2: Set Theory and Functions
    8 questions
    Use Quizgecko on...
    Browser
    Browser