Answer to Question #302616 in Discrete Mathematics for Jayson

Question

1. Let A = { 2, 3 }, and B = { 3, 4, 5, 6 }

Let R be a relation from A to B where

R = {(x, y) “x exactly divides y”}

Enumerate the following:

A. elements of R; R = { ______, ______, ______, ______ }

rewrite R as a table.

A B

2. Let R be a relation on A = { 1, 2, 3 } defined by

R = { (x, y) l x ≤ y ˄ x, y ∈ A }

Identify the domain and range of the relation R.

Answer 1

Solution:

(1) Let A = { 2, 3 }, and B = { 3, 4, 5, 6 }

R = {(x, y) “x exactly divides y”} = {(2,4),(2,6),(3,3),(3,6)}

R as a table:

A B

2 4

2 6

3 3

3 6

(2) Let R be a relation on A = { 1, 2, 3 } defined by

R = { (x, y) l x ≤ y ˄ x, y ∈ A }

R = {(1,1), (1,2), (1,3), (2,2), (2,3), (3,3)}

Domain = {1,2,3}

Range = {1,2,3}