Etymology of Cosine
Date: 5/21/96 at 11:4:2 From: Anonymous Subject: Cosine I am writing to find out who/where cosine came from. I found out about sine from Dr. Math, but I didn't see anything about cosine. Could you help me? Kenny Allen
Date: 7/2/96 at 22:15:51 From: Doctor Robert Subject: Re: Cosine The word cosine is short for "complementary sine". You will notice that the cosine of an acute angle is always equal to the sine of that angle's complement. For example, cos 60 = sin 30, or cos 27 = sin 63. -Doctor Robert, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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