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Step * 1 2 1 of Lemma two-mul


1. x : ℤ
⊢ x + x ~ x + x
BY
{ SqReflexive }

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Latex:

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Latex:

1.  x  :  \mBbbZ{}
\mvdash{}  x  +  x  \msim{}  x  +  x


By

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Latex:
SqReflexive

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