Identifiers of General Constants, Variables and Functions

Q

How to use <mi> to represent identifiers of general constants, variables and functions?

✍: FYIcenter.com

A

"ISO 80000-2 Quantities and Units - Mathematics" specifies that identifiers of general constants, variables and functions should be presented in italic style.

The <mi> tag takes a single letter and is rendered in italic. This meets the above ISO 80000-2 specification correctly. For example:

<math><mi>f</mi><mo>⁡</mo><mo>(</mo><mi>x</mi><mo>)</mo>
  <mo>=</mo><mi>a</mi><msup><mi>x</mi><mn>2</mn></msup>
  <mo>+</mo><mi>b</mi><mi>x</mi><mo>+</mo><mi>c</mi></math>
     $f (x) = a x^{2} + b x + c$

Note that multi-letter descriptive names or abbreviations should not be used as identifiers. So the following example is not recommended:

<math><mi mathvariant="normal">π</mi><mo>&#x2254;</mo>
  <mfrac><mi>Circumference</mi><mi>Diameter</mi></mfrac></math>
     $π ≔ \frac{Circumference}{Diameter}$

⇒ Identifiers of Well-Known Entities

⇐ ISO 80000-2 Quantities and Units - Mathematics

⇑ ISO 80000-2 Quantities and Units - Mathematics

⇑⇑ MathML (Mathematical Markup Language)

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