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Name: Laramy
Status: educator
Grade: 9-12
Location: GA
Country: USA
Date: N/A 

I read your response to why we use the letter x in Algebra, but my question is why we use the Greek letter Theta in Trigonometry to represent an angle?


It is just a convention. Nothing really dictates that folks use theta to represent angles in trigonometry. But when a lot of folks use the same letter the same way it increases understanding about what is being talked about.

It is like, "Why does a red traffic light mean stop and a green light mean go? Why is it not the other way around?" This has become an international convention so people can drive in other countries without having to learn new rules all of the time.

Sincere regards,
Mike Stewart

To my knowledge, there is nothing special about the Greek letter Theta. Greek letters are commonly used vs. Roman script to distinguish "variables" and "constants", but even that does not have any particular significance.

Vince Calder

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