Law of Sines and Law of Cosines: Introduction

Greek Mathematician and Astronomer Claudius Ptolemy

Imagine what life was like before many of the great scientific discoveries, before the knowledge that the earth revolved around the sun or even that the earth was round.  In math classes today, you are taught many important rules and theorems.  All theses theorems and rules were once unknown.  Imagine the minds that discovered these theorems and properties.  Each step in your mathematical journey gives you more and more skills that can be applied to the career path you choose to take, but none of it would be possible without the great mathematicians that came before you.  One great mathematician and astronomer was Claudius Ptolemy.  He had a hand in developing the two laws you will learn in this section, the Law of Sines and the Law of Cosines.