Relations

Author:NCERT
11th CBSE
IMPORTANT

Relations: Overview

This topic defines the concept of relations with help of examples. We will also learn to calculate the domain and range for relations. Practice exercises are given here for our better understanding.

Important Questions on Relations

EASY
IMPORTANT

Let A=1, 2, 3, 4, 6. Let R be the relation on A defined by {(a, b):a, bA, b is exactly divisible by a}. Find the number of elements in the set of range of R.

MEDIUM
IMPORTANT

Let A=1, 2, 3, 4, 6. Let R be the relation on A defined by {(a, b):a, bA, b  is exactly divisible by a}. Find the number of elements in the domain of R.

EASY
IMPORTANT

Let A=x,y,z and B=1,2. Find the number of relations from A to B.

EASY
IMPORTANT

Write the relation R={(x,x3):xisaprimenumberlessthan10} in roster form.

MEDIUM
IMPORTANT

Let A=1, 2, 3, 4, 6. Let R be the relation on A defined by {(a, b):a, bA, b  is exactly divisible by a}.
Write R in roster form
 

MEDIUM
IMPORTANT

The figure shows a relationship between the sets P and Q. Write this relation
 In set-builder form. What is it’s domain and range?
Question Image

EASY
IMPORTANT

A={1, 2, 3, 5} and B=4, 6, 9. Define a relation R from A to B by R={(x, y): the difference between x and y is odd; xAyB}. Write R in roster form.

MEDIUM
IMPORTANT

Define a relation R on the set N of natural numbers by
R={x, y : y=x+5, x is a natural number less than 4; x, yN}. Depict this relationship using roster form. Write down the domain and the range.

MEDIUM
IMPORTANT

Let A={1, 2, 3,....,14}. Define a relation R from A to A by R={(x, y) : 3x-y=0,wherex, yA}. Write down its domain, codomain and range.