Question

Suppose R is a symmetric and transitive relation on a set A, and there is an element a in A for which aRx for every x in A. Prove that R is reflexive. ...?

Answer 1

According to what I have researched, here is how you prove that R is reflexive.
let b∈A
then, aRb
and by symmetry, bRa
and by transitivity,bRa,aRb⇒bRb
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