Let S be the set of all points in a plane and let R be a relation in S

1.	Let S be the set of all points in a plane and let R be a relation in S defined by R = {(A, B): d(A, B) < 2 units}, where d(A, B) is the distance between the points A and B.Show that R is reflexive and symmetric but not transitive.
Answer» (i) Reflexive- d(A, A) < 2 we get (A, A) ∈ R (ii) Symmetric- (A, B) ∈ R We get d (A, B) < 2 and d (B, A) < 2 So (B, A) ∈ R (iii) Transitive- If A (0, 0), B (1.5, 0) and C (3, 0) are the point s we get d (A, B) = 1.5, d (B, C) = 1.5 and d (A, C) = 3 So we get d (A, C) < 2 is not true Therefore, R is reflexive and symmetric but not transitive.

Let S be the set of all points in a plane and let R be a relation in S defined by R = {(A, B): d(A, B) < 2 units}, where d(A, B) is the distance between the points A and B.Show that R is reflexive and symmetric but not transitive.

Answer»

(i) Reflexive-

d(A, A) < 2 we get (A, A) ∈ R

(ii) Symmetric-

(A, B) ∈ R

We get

d (A, B) < 2 and d (B, A) < 2

So (B, A) ∈ R

(iii) Transitive-

If A (0, 0), B (1.5, 0) and C (3, 0) are the point s we get

d (A, B) = 1.5, d (B, C) = 1.5 and d (A, C) = 3

So we get

d (A, C) < 2 is not true

Therefore, R is reflexive and symmetric but not transitive.

Discussion

No Comment Found

Related InterviewSolutions

In fig. shows a relationship between the sets P and Q. Write this relation in :a. Set builder form b. Roster form c. What is its domain and range?
Let A = {1, 2, 3, 4, 5, 6}. Let R be a relation on A defined by R = {(a, b): a, b A, b is exactly divisible by a} i. Write R in roster form ii. Find the domain of R iii. Find the range of R.
Let `A = {1, 2, 3, 4, 6}`. Let R be the relation on A defined by `{(adot b): a , b in A , b`is exactly divisible by a}.(i) Write R in roster form(ii) Find the domain of R(iii) Find the range of R.
Let `A={1,2,3,5}" and "B={4,6,9}.` Define a relation from A to B, given by `R={(a,b):a inA,b inB" and "(a-b)" is odd"}.` (i) Write R in roster form. (ii) Find dom (R) and range (R).
Show that the relation R on the set Z of integers, given by R = {(a, b) : 2 divides a – b}, is an equivalence relation.
Let W denote the words in the English dictionary. Let the relation R be defined by R = {(x, y) ∈ W × W : the words x and y have at least one letter in common}. Then R is (a) Reflexive and transitive, not symmetric (b) Reflexive and symmetric and not transitive (c) Symmetric and transitive, not reflexive (d) Reflexive, symmetric and transitive
Given the relation R = {(1, 2), (2, 3)} on the set A = {1, 2, 3}, the minimum number of ordered pairs which can be added to R to make it an equivalence relation is(a) 2 (b) 3 (c) 5 (d) 7
If R be a relation defined as a R b ⇔ | a | < b, then R is(a) Reflexive only (b) Symmetric only (c) Transitive only (d) Reflexive and transitive but not symmetric
Let I be the set of integers and R be a relation on I defined by R = {(x, y) : (x – y) is divisible by 11, x, y ∈ I}. Then R is(a) An equivalence relation (b) Symmetric only (c) Reflexive only (d) Transitive only
Let Z be the set of integers. Then the relation R = {(a, b) : a, b ∈ Z and (a + b) is even} defined on Z is(a) Only symmetric (b) Symmetric and transitive only (c) An equivalence relation (d) None of the above

Let S be the set of all points in a plane and let R be a relation in S defined by R = {(A, B): d(A, B) &lt; 2 units}, where d(A, B) is the distance between the points A and B.Show that R is reflexive and symmetric but not transitive.

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment

Let S be the set of all points in a plane and let R be a relation in S defined by R = {(A, B): d(A, B) < 2 units}, where d(A, B) is the distance between the points A and B.Show that R is reflexive and symmetric but not transitive.