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trigonometric function

vr.tr.trigonometric-function · thing-q93344

Let an agent explain the trigonometric functions and their relations, relay identities, values and applications from mathematical references, describe historical and rarely used functions, and distinguish trigonometric from hyperbolic and inverse functions.

Thing Registry Cross-cutting context XCT.QLT

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Define Definitions.

Definition

Definitions.

Definition

Definition.

  1. How are the trigonometric functions defined by triangles, the unit circle and series? definition
  2. Is the question about trigonometric, inverse or hyperbolic functions? boundary

Relations

Identities.

Relations

Relations.

  1. What are the key identities, including Pythagorean, angle sum and double angle formulas? definition
  2. Which entry fits trigonometric identity? action
Compute Values and computation.

Values

Special values and graphs.

Values

Values.

  1. What are the special values and graph features of each function? measurement
  2. Which references are standard? provenance

Algorithms

Computation.

Algorithms

Algorithms.

  1. How are trigonometric functions computed by series, CORDIC and tables? provenance
  2. Which entry fits CORDIC? action
Apply Applications.

Physics

Physics and engineering.

Physics

Physics.

  1. How are trigonometric functions used in waves, rotations, navigation and signal processing? provenance
  2. Which entry fits Fourier analysis? action

Historical

Historical and rare functions.

Historical

Historical.

  1. What were the chord, versine and haversine used for, and what is the cas function? provenance
  2. Which sources are cited? provenance
Context History and teaching.

History

History.

History

History.

  1. How did trigonometry develop from Hipparchus and Indian sine tables to Euler? provenance
  2. Which entry fits the history of trigonometry? action

Teaching

Teaching.

Teaching

Teaching.

  1. How are trigonometric functions taught, and what misconceptions arise? provenance
  2. Which entry fits mathematics education? action

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.QLT
Other names and narrower kinds
cas function, chord function, tangent and cotangent, sine and cosine, secant and cosecant, rarely used trigonometric functions, Jyā, koti-jyā and utkrama-jyā

What it is Filled

The functions of an angle that relate the angles of a right triangle to ratios of its sides and extend through the unit circle beyond acute angles, principally sine and cosine, tangent and cotangent, secant and cosecant, with historically used functions such as the chord, versine and haversine, and the cas function of the Hartley transform; sine and cosine are defined for every real input, tangent and secant are undefined where cosine is zero, and cotangent and cosecant are undefined where sine is zero. Trigonometric functions are periodic, elementary and transcendental, and are fundamental in geometry, physics, signal processing and engineering.

Why it exists Filled

Let an agent explain the trigonometric functions and their relations, relay identities, values and applications from mathematical references, describe historical and rarely used functions, and distinguish trigonometric from hyperbolic and inverse functions.

Distinguishing features Filled

  • Unit circle definition
  • Periodicity
  • Rich identities
  • Fourier basis

What robots and AI may and may not do Filled

Must not

  • Mix degrees and radians silently in a calculation.
  • Return an inverse value outside its principal range without saying so.
  • Present a rounded value as exact in navigation, surveying or engineering results.
  • Hide a division by zero, such as tangent at a right angle, behind a large number.

Only with a human decision

  • Relying on its own trigonometric calculations for structural, navigation or safety-critical work.

May

  • Compute sine, cosine, tangent and related functions and state whether angles are in degrees or radians.
  • Explain identities and inverse functions with their valid ranges.

Moral aspects Filled

  • Angle errors in surveying, navigation and construction can cause accidents and boundary disputes.
  • Students rely on worked answers; wrong ones mislead learning.

Who is affected

  • Engineers and surveyors
  • Students
  • People relying on computed positions

Owners Filled

Steward

The public: held in common as mathematical knowledge.

Links to other meta-models Filled

parent

  • Q184743 - registry parent class
  • Q824282 - registry parent class
  • Q864333 - registry parent class

related

  • periodic function - in registry terms
  • elementary function - in registry terms
  • transcendental function - in registry terms
  • unit circle - for all real arguments

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.trigonometric-function
  • Wikidata: Q93344 (https://www.wikidata.org/wiki/Q93344)

Direct properties not applicable Not applicable

  • period of sine: 2 pi radians
  • principal functions: 6 count

Plane XCT: no invented physical properties.

Recognition optional Filled

  • Functions of angles based on the unit circle
  • Sine, cosine, tangent, cotangent, secant, cosecant and historical functions
  • Hyperbolic functions use the hyperbola; inverse trigonometric functions return angles
  • Wave-shaped graphs of sine and cosine and the unit circle diagram.

Capabilities and actions required Filled

  • explain definitions and relations
  • relay identities and values
  • describe applications
  • distinguish related functions

Hazards and failure modes required Filled

  • Degree and radian confusion
  • Notation ambiguities such as sin squared and inverse
  • Domain errors for tangent and secant

Standards and interfaces required Filled

  • ISO 80000-2 notation for trigonometric functions
  • No regulation

Context of use required Filled

  • Relating angles to lengths and modelling periodic phenomena.
  • sine and cosine
  • tangent and cotangent
  • secant and cosecant
  • historical functions such as chord, versine, haversine and exsecant
  • the cas function
  • inverse trigonometric functions as related
  • hyperbolic analogues as related

Sources Filled

  1. Wikidata item Q93344: trigonometric function - identity and sense of the item
  2. Wikipedia: Trigonometric functions - general description of the item

Open questions

  • Should sine and cosine be the primary linked entries?
  • How should reference tables be linked?
  • The registry entry has merged aliases naming pairs and rare functions; should they be split off?

Machine files

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q93344/spec.json