Category:Triangle Inequality

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This category contains results about the Triangle Inequality.


Triangle Inequality on Metric Space

Recall the metric space axioms:

\((\text M 1)\)   $:$     \(\ds \forall x \in A:\) \(\ds \map d {x, x} = 0 \)      
\((\text M 2)\)   $:$   Triangle Inequality:      \(\ds \forall x, y, z \in A:\) \(\ds \map d {x, y} + \map d {y, z} \ge \map d {x, z} \)      
\((\text M 3)\)   $:$     \(\ds \forall x, y \in A:\) \(\ds \map d {x, y} = \map d {y, x} \)      
\((\text M 4)\)   $:$     \(\ds \forall x, y \in A:\) \(\ds x \ne y \implies \map d {x, y} > 0 \)      


Axiom $\text M 2$ is referred to as the triangle inequality, as it is a generalization of the Triangle Inequality which holds on the real number line and complex plane.


Triangle Inequality on Normed Vector Space

Recall the vector space norm axioms:

\((\text N 1)\)   $:$   Positive Definiteness:      \(\ds \forall x \in V:\)    \(\ds \norm x = 0 \)   \(\ds \iff \)   \(\ds x = \mathbf 0_V \)      
\((\text N 2)\)   $:$   Positive Homogeneity:      \(\ds \forall x \in V, \lambda \in R:\)    \(\ds \norm {\lambda x} \)   \(\ds = \)   \(\ds \norm {\lambda}_R \times \norm x \)      
\((\text N 3)\)   $:$   Triangle Inequality:      \(\ds \forall x, y \in V:\)    \(\ds \norm {x + y} \)   \(\ds \le \)   \(\ds \norm x + \norm y \)      


Axiom $\text N 3$ is referred to as the triangle inequality, as it is a generalization of the Triangle Inequality which holds on the real number line and complex plane.


Triangle Inequality on Matrix Space

Recall the matrix norm axioms:

\((\text N 1)\)   $:$   Positive Definiteness:      \(\ds \forall \mathbf A \in \map {\MM_\GF} {m, n}:\)    \(\ds \norm {\mathbf A} = 0 \)   \(\ds \iff \)   \(\ds \mathbf A = \mathbf 0_{m, n} \)      where $\mathbf 0_{m, n}$ denotes the zero matrix of order $m \times n$
\((\text N 2)\)   $:$   Positive Homogeneity:      \(\ds \forall x \in \map {\MM_\GF} {m, n}, \lambda \in \GF:\)    \(\ds \norm {\lambda \mathbf A} \)   \(\ds = \)   \(\ds \norm \lambda \times \norm {\mathbf A} \)      where $\norm \lambda$ denotes the (division ring) norm of $\lambda$
\((\text N 3)\)   $:$   Triangle Inequality:      \(\ds \forall \mathbf A, \mathbf B \in \map {\MM_\GF} {m, n}:\)    \(\ds \norm {\mathbf A + \mathbf B} \)   \(\ds \le \)   \(\ds \norm {\mathbf A} + \norm {\mathbf B} \)      


Axiom $\text N 3$ is referred to as the triangle inequality, as it is a generalization of the Triangle Inequality which holds on the real number line and complex plane.

Subcategories

This category has the following 2 subcategories, out of 2 total.

Pages in category "Triangle Inequality"

The following 51 pages are in this category, out of 51 total.