RadiansDate: 9/2/96 at 22:52:58 From: Mohd Nasir Mahmud Subject: Radians Dear Sir, Could you tell me why pi radians = 180 degrees? Date: 10/24/96 at 16:5:50 From: Doctor Jaime Subject: Radians This is an immediate consequence of the definition of radians and degrees. In fact 1 radian is defined as the central angle subtended by the arc of length 1 on a unit circle. 1 degree is the central angle subtended by (1/360)th of the circumference of a unit circle. This measure dates back to the Babylonians, who used a base 60 number system. Since the circumference of the unit circle is 2 Pi, it follows that there are 2 Pi radians in 360 degrees, or Pi radians = 180 degrees. -Doctor Jaime, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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