# Spherical Laws of Sines and Cosines/Mistake

## Source Work

2008: Ian Stewart: *Taming the Infinite*:

- Chapter $5$: Eternal Triangles: Trigonometry and logarithms
- Early trigonometry

This mistake can be seen in the $2008$ edition as published by Quercus: ISBN 978-1-84724-768-1

## Mistake

- "He [that is, Georg Joachim Rhaeticus] stated the law of sines for spherical triangles ... and the
*law of cosines*... in his*De Triangulis*, written in 1462-3 but not published until 1533."

The book *De Triangulis (Omnimodus)* was in fact by Johannes Müller von Königsberg ("Regiomontanus") and was actually published in 1464.