About

About Trigonify

Trigonify is for students working through trigonometry. It collects 45 identities in 16 topics, each on a page of its own with worked uses, and adds an interactive unit circle, a solver that shows each step, and a practice bank.

The topics run Basics, Pythagorean, Reciprocal, Quotient, Even/Odd, Cofunction, Law of Sines, Law of Cosines, Area, Inverse, Sum & Difference, Double Angle, Half Angle, Power Reduction, Product to Sum, Sum to Product, in that order, from the basic definitions through to the identities that turn sums of sines and cosines into products.

Who makes it

Trigonify is made by an independent developer working alone, who also makes CalcRef, PhysRef, StatRise and OpticBench. Saying so here, in plain text, is the whole point of this paragraph: they are one person's sites, not separate publishers. No faculty or teacher is named on any page.

How the identity reference is built

The identities are generated from the content files of the Trigonify mobile app by a script in this repository. Each one is a single record holding one LaTeX expression, and the identity pages and topic pages render that record rather than a retyped copy. Algebra in the guides is typeset by the same renderer, never pasted in as an image.

Guide bylines and dates

The guides are published under the Trigonify name and carry no individual byline. The structured data on each lists the Trigonify organization as author. Every guide shows the date its text was last changed.

What it cannot do

Trigonify is a study aid, not a replacement for your course or your teacher. An identity holds only where its terms are defined, and the solver works the input you give it; it cannot tell whether that input is the right setup for your problem.

Corrections

Found an identity, a step or a guide that is wrong? Email [email protected] and say which page. Privacy is covered on its own page, as are the terms.