Product of Positive Element and Element Greater than One

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Theorem

Let $\struct {R, +, \circ, \le}$ be an ordered ring with unity $1_R$ and zero $0_R$.

Let $x, y \in R$.

Suppose that $x > 0_R$ and $y > 1_R$.


Then $x \circ y > x$ and $y \circ x > x$.


Proof

\(\ds y\) \(>\) \(\ds 1_R\)
\(\ds x \circ y\) \(>\) \(\ds x \circ 1_R\) $x > 0_R$, Properties of Ordered Ring: $(6)$
\(\ds x \circ y\) \(>\) \(\ds x\) Definition of Unity of Ring

A similar argument shows that $y \circ x > x$.

$\blacksquare$