Tag Archives: sine

Trigonometry lesson, 2

In the previous post on trigonometry I explained the strange chain of circumstances that led to the Latin word “sinus” (meaning a bay or inlet, or alternatively a bosom) came to be used for the ratio of the half-chord of … Continue reading

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Trigonometry lesson

This is not a lesson about trigonometry. But where did the names sine, cosine, and the rest of them come from? First, there is no mystery about the prefix “co”. Each cofunction of an angle θ is the function of … Continue reading

Posted in exposition, history | Tagged , , | 7 Comments