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Wild Trig - An Introduction to Rational Trigonometry

Insights into Mathematics via YouTube

Overview

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Explore a comprehensive video series that introduces Rational Trigonometry, a revolutionary algebraic approach to trigonometry that replaces traditional angles, sines, and cosines with simple high school algebra. Discover how this innovative framework, developed by Professor N J Wildberger in his 2005 book "Divine Proportions," uses quadrance instead of distance and spread instead of angles to make trigonometric calculations more computationally efficient and mathematically sensible. Learn the five main laws of Rational Trigonometry and see how they apply to solving triangles, understanding circle geometry, and tackling real-world problems in surveying and astronomy. Delve into advanced topics including projective geometry, chromogeometry (red and green geometries), barycentric coordinates, and applications to special relativity. Master the use of determinants in geometry, explore triangle centers and properties through rational methods, and understand how this approach connects naturally to linear algebra and opens new research directions in higher-dimensional and hyperbolic geometries. Examine practical applications from pentagon constructions to ladder problems, while gaining insights into the philosophical foundations of geometry and mathematics education. Progress through systematic coverage of finite field trigonometry, spread polynomials, Pythagorean triples, and isometry groups, culminating in a deep understanding of how Rational Trigonometry provides a more elegant and computationally powerful alternative to classical trigonometric methods across various number systems and geometric contexts.

Syllabus

Why Trig is Hard | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Quadrance via Pythagoras and Archimedes | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Spread, Angles and Astronomy | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Five Main Laws of Rational Trigonometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Applications of Rational Trigonometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Heron's Formula Viewed Rationally | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Solving Triangles with Rational Trigonometry | WildTrig: Intro to Rational Trigonometry
Centers of Triangles with Rational Trigonometry | WildTrig: Intro to Rational Trigonometry
Laws of Proportion for a Triangle | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Geometry of Circles with Rational Trigonometry | WildTrig: Intro to Rational Trigonometry
Applications of rational trig to surveying (I) | WildTrig | N J Wildberger
Cartesian coordinates and geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Why spreads are better than angles | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Rational parameters for circles | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Complex numbers and rotations | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Rational Trigonometry Quiz 1 | WildTrig: Intro to Rational Trigonometry | N J Wildberger
An Invitation to Geometry | WildTrig: Intro to Rational Trigonometry 0 | N J Wildberger
Rational trigonometry: Solutions to Quiz (1) WildTrig: Intro to Rational Trigonometry
Medians, altitudes and vertex bisectors | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Trigonometry with finite fields (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Trigonometry with Finite Fields (II) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Trigonometry with Finite Fields (III) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Highlights from triangle geometry (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Highlights from triangle geometry (II) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Spread polynomials | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Pentagons and five-fold symmetry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Applications of rational trig to surveying (II) | WildTrig: Intro to Rational Trigonometry
Stewart's theorem | WildTrig: Intro to Rational Trigonometry | N J Wildberger
What size ladder fits around a corner? | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Trisecting angles and Hadley's theorem | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Polar coordinates and rational trigonometry | WildTrig: Intro to Rational Trigonometry
Introduction to Projective Geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Projective geometry and perspective | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Projective geometry and homogeneous coordinates | WildTrig: Intro to Rational Trigonometry
Lines and planes in projective geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Affine geometry and barycentric coordinates | WildTrig: Intro to Rational Trigonometry
The cross ratio | WildTrig: Intro to Rational Trigonometry | N J Wildberger
More about the cross ratio | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Affine geometry and vectors | WildTrig: Intro to Rational Trigonometry | N J Wildberger
The fundamental theorem of projective geometry | WildTrig: Intro to Rational Trigonometry
Harmonic ranges and pencils | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Conics via projective geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
How to learn mathematics | WildTrig: Intro to Rational Trigonometry | N J Wildberger
An algebraic framework for rational trigonometry (II) | WildTrig: Intro to Rational Trigonometry
An algebraic framework for rational trigonometry (I) | WildTrig: Intro to Rational Trigonometry
Einstein's special relativity: an introduction | WildTrig: Intro to Rational Trigonometry
Red geometry (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Red geometry (II) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Red geometry (III) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Circles in red geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Green geometry (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Green geometry (II) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Pythagorean triples | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Chromogeometry and Euler lines | WildTrig: Intro to Rational Trigonometry | N J Wildberger
An introduction to chromogeometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Chromogeometry and the Omega triangle | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Chromogeometry and nine-point circles | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Proofs in chromogeometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Triangle spread rules | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Triangle spread rules in action | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Acute and obtuse triangles | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Proofs of the Triangle spread rules | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Rational trigonometry Quiz (#2) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Hints for solutions to Quiz (#2) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
The 6-7-8 triangle | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Barycentric coordinates and the 6-7-8 triangle | WildTrig: Intro to Rational Trigonometry
Squares in a pentagon | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Trisecting a right triangle | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Euler's Four Point Relation | WildTrig: Intro to Rational Trigonometry | N J Wildberger
What is geometry really about? | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Determinants in geometry (II) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Determinants in geometry (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Determinants in Geometry (III) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Spreads, determinants and chromogeometry (I) | WildTrig: Intro to Rational Trigonometry
Spreads, determinants and chromogeometry (II) | WildTrig: Intro to Rational Trigonometry
Spreads, determinants and chromogeometry (III) | WildTrig: Intro to Rational Trigonometry
Coloured spreads and generalizations (I) | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Coloured spreads and generalizations (II) | WildTrig: Intro to Rational Trigonometry
Geometry with a general dot product | WildTrig: Intro to Rational Trigonometry | N J Wildberger
The general rational laws of trigonometry | WildTrig: Intro to Rational Trigonometry
Maths education and rational trigonometry (I) | WildTrig: Intro to Rational Trigonometry
Rheticus and 17th century trig tables | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Maths Education and Rational Trigonometry (II) | WildTrig: Intro to Rational Trigonometry
Maths Education and Rational Trigonometry (III) | WildTrig: Intro to Rational Trigonometry
Rational trigonometry and mathematics education (IV) | WildTrig: Intro to Rational Trigonometry
The true role of the circular functions | WildTrig: Intro to Rational Trigonometry | N J Wildberger
Understanding uniform motion: are radians really necessary? | WildTrig
Turn angles, continued fractions and approximate geometry | WildTrig: Intro to Rational Trigonometry
Isometry groups in planar geometry | WildTrig: Intro to Rational Trigonometry | N J Wildberger
The Euclidean rotation group and complex number multiplication | WildTrig
The geometry of Euclidean reflections and rotations (grounded!) | WildTrig
Half-slope and the full group of Euclidean isometries | WildTrig: Intro to Rational Trigonometry
The group of blue planar isometries | WildTrig: Intro to Rational Trigonometry | N J Wildberger

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