Definition:Strictly Negative

Definition
Let $\left({R, +, \circ, \le}\right)$ be an ordered ring whose zero is $0_R$.

Then $x \in R$ is strictly negative iff $x \le 0_R$ and $x \ne 0_R$.

The set of all strictly negative elements of $R$ is denoted:


 * $R_-^* := \left\{{x \in R: x \le 0_R \land x \ne 0_R}\right\}$