Using the Laws of Sine and CosineDate: 9/24/95 at 20:45:58 From: Anonymous Subject: trigonometry How do I find the sine and cosine of pi/12? Date: 9/24/95 at 21:38:59 From: Doctor Andrew Subject: Re: trigonometry Since pi/12 = pi/3 - pi/4 you can use the formulas: cos(a+b) = cos(a)cos(b) - sin(a)sin(b) sin(a+b) = sin(a)cos(b) + cos(a)sin(b) with a = pi/3 and b = -pi/4. Have a blast! -Doctor Andrew, The Geometry Forum |
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