Checking relation symmetry confusion

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Let S = {1, 2} and define ρ and µ be relations on S defined by

$ρ = \{(1, 1),(1, 2),(2, 1)\}$

$µ = \{(1, 1),(2, 2)\}$

Is $ρ$ symmetric? To determine if a relation is symmetric, we need to check if whenever (a, b) is in the relation, (b, a) is also in the relation. In this case $ρ$ is symmetric right? Since

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but for $µ$, this is not symmetric right?

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Also I am confused about anti-symmetry. here is my working:

For the relation ρ = {(1, 1), (1, 2), (2, 1)}:

(1, 2) is in ρ, but (2, 1) is also in ρ. Since (1, 2) ≠ (2, 1), ρ is not antisymmetric.

For the relation µ = {(1, 1), (2, 2)}:

(1, 1) is in µ, and (2, 2) is also in µ. Thus, µ is antisymmetric. But I am still confused about this.