Problem 10.2. Let R be a relation on the set X (so $R \subseteq X \times X$). a) Show that the following are equivalent: (i) The relation R is both symmetric and anti-symmetric. (ii) We have $R \subseteq \Delta_X := \{(x, x) \mid x \in X\}$. b) Show that the following are equivalent: (i) The relation R is both an equivalence relation and a partial ordering. (ii) We have $R = \Delta_X$. c) Show: if X has at least two elements, there is no relation on R that is both an equivalence relation and a total ordering.
Added by Rita W.
Close
Your feedback will help us improve your experience
Hoan Nguyen and 91 other Calculus 3 educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
A certain relation * is defined on the set R^2 by (x1, x2) * (y1, y2) if and only if there exists a real number 0 < k <= 1 such that y2 = kx1 and x2 = ky1. For each of the following questions, be sure to provide a proof supporting your answer. a) Is * reflexive? b) Is * symmetric? c) Is * anti-symmetric? d) Is * transitive? e) Is * an equivalence relation, a partial order, both, or neither?
Hoan N.
If ' $R$ ' is a relation in a set $X$ such that $R^{-1}=R$, then the relation $R$ is (A) Transitive (B) Anti-symmetric (C) Symmetric (D) None of these
Engineering Mathematics
Set Theory and Algebra
Let R be a relation on a set U. State the definitions of the following: (a) R is reflexive. (b) R is symmetric. (c) R is antisymmetric. (d) R is transitive. (e) R is an equivalence relation. (f) R is a partial ordering.
Rukhmani J.
Recommended Textbooks
Calculus: Early Transcendentals
Thomas Calculus
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD