[TIB] Re: TI-HAKMEM (degrees vs. radians)


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[TIB] Re: TI-HAKMEM (degrees vs. radians)





Listar wrote:
> ------------------------------
>
> From: "Aaron Fineman" <amfineman@earthlink.net>
> Subject: [TIB] Re: TI-HAKMEM
> Date: Sat, 7 Sep 2002 17:43:28 -0400
>
>
>     I believe radians are default. I haven't played around with that much.
> What's the difference between radians and degrees?
>

  One radian is about 57 degrees; that is, 2*pi radians equals
exactly 360 degrees equals exactly one revolution.
  Degrees are easy for most people to grasp, because they make
nice numbers for common angles (like 30 and 45 degrees).  But
radians are used exclusively in most mathematical applications
because they have special characteristics.

  integral ( sin x )  =  cos x

  derivative ( sin x ) dx  =  - cos x

when x is measured in radians, for example.  And the length of
an arc of a circle is equal to (radius) times (angle measure)
when (angle measure) is measured in radians.  For this reason,
it can be said that measures in radians "have no units."

 -Arthur