Problem 4 Let A be a set, and let R be a relation on A. 1. Suppose R is reflexive. Prove that ∪x∈A[x] = A. 2. Suppose R is symmetric. Prove that x ∈[y] if and only if y ∈[x], for all x, y ∈A. 3. Suppose R is transitive. Prove that if xRy, then [y] ⊆[x] for all x, y ∈A.

Problem 4 Let A be a set, and let R be a relation on A. 1. Suppose R is reflexive. Prove that ∪x∈A[x] = A. 2. Suppose R is symmetric. Prove that x ∈[y] if and only if y ∈[x], for all x, y ∈A. 3. Suppose R is transitive. Prove that if xRy, then [y] ⊆[x] for all x, y ∈A.

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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