- #1
jwxie
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Given A = {1,2,3}
R1 = {1,1 2,2 3,3}
I know it is reflexive, and I know it is symmetric. But what about its transitivity?
Def of transitive: a,b in R, b,c in R, then a,c is also in R
let a = 1
let b = 1
let c = 1
(1,1) and (1,1)
So yes, the book says it is an equivalence relation, so its transitivity is also valid.
therefore, are all reflexive relations transitive?
but what if the questions asks: constructs a reflexive and sysmmetric but not transitive?
I can do 11 22 33 and add 12 21 to make them both reflexive and symmetric. since i added 12 and 21, thus these 2 ordered pairs destroyed the transitivity?
R1 = {1,1 2,2 3,3}
I know it is reflexive, and I know it is symmetric. But what about its transitivity?
Def of transitive: a,b in R, b,c in R, then a,c is also in R
let a = 1
let b = 1
let c = 1
(1,1) and (1,1)
So yes, the book says it is an equivalence relation, so its transitivity is also valid.
therefore, are all reflexive relations transitive?
but what if the questions asks: constructs a reflexive and sysmmetric but not transitive?
I can do 11 22 33 and add 12 21 to make them both reflexive and symmetric. since i added 12 and 21, thus these 2 ordered pairs destroyed the transitivity?