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| isaac |
 Posted: Fri Apr 25, 2008 7:23 pm |
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Why the angle x in the power series for Cos[x] and Sin[x] etc... is
taken in radian where does this comes from? |
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| Mariano Suárez-Alvarez |
| Posted: Fri Apr 25, 2008 7:35 pm |
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On Apr 26, 2:23 am, isaac <davidbh...@gmail.com> wrote:
Quote: Why the angle x in the power series for Cos[x] and Sin[x] etc... is
taken in radian where does this comes from?
Because the functions those power series represent
take their arguments in radians.
-- m |
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| Mariano Suárez-Alvarez |
| Posted: Sat Apr 26, 2008 1:32 am |
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On Apr 26, 5:51 am, William Elliot <ma...@hevanet.remove.com> wrote:
Quote: On Sat, 26 Apr 2008, Tim Little wrote:
On 2008-04-26, isaac <davidbh...@gmail.com> wrote:
Why the angle x in the power series for Cos[x] and Sin[x] etc... is
taken in radian where does this comes from?
You can write a power series where x is in degrees if you want. It
will be a different power series, full of lots of horrible constants
expressed in terms of powers of pi and 180 and factorials. I wouldn't
want to use such an ugly power series, but you can do it if you want.
In short, it's for elegance and simplicity.
It's because it's calculus and not engineering.
Engineers are very able to compute
sin (pi x / 180) !
-- m |
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| Tim Little |
| Posted: Sat Apr 26, 2008 3:23 am |
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On 2008-04-26, isaac <davidbhatt@gmail.com> wrote:
Quote: Why the angle x in the power series for Cos[x] and Sin[x] etc... is
taken in radian where does this comes from?
You can write a power series where x is in degrees if you want. It
will be a different power series, full of lots of horrible constants
expressed in terms of powers of pi and 180 and factorials. I wouldn't
want to use such an ugly power series, but you can do it if you want.
In short, it's for elegance and simplicity.
- Tim |
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| William Elliot |
| Posted: Sat Apr 26, 2008 3:51 am |
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On Sat, 26 Apr 2008, Tim Little wrote:
Quote: On 2008-04-26, isaac <davidbhatt@gmail.com> wrote:
Why the angle x in the power series for Cos[x] and Sin[x] etc... is
taken in radian where does this comes from?
You can write a power series where x is in degrees if you want. It
will be a different power series, full of lots of horrible constants
expressed in terms of powers of pi and 180 and factorials. I wouldn't
want to use such an ugly power series, but you can do it if you want.
In short, it's for elegance and simplicity.
It's because it's calculus and not engineering.
These derivates are used for the series:
d(sin x)/dx = cos x; d(cos x)/dx = -sin x.
Now if x is measured in degrees instead of radians,
d(sin x)/dx = pi.(cos x)/180 |
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| A N Niel |
| Posted: Sat Apr 26, 2008 2:37 pm |
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In article
<f6df4487-a9f5-4aaa-9153-48e5792ec083@59g2000hsb.googlegroups.com>,
Mariano Suárez-Alvarez <mariano.suarezalvarez@gmail.com> wrote:
Quote: Engineers are very able to compute
sin (pi x / 180) !
Factorial of sine, wow. |
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| Rob Johnson |
| Posted: Sat Apr 26, 2008 4:13 pm |
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In article <260420081537395712%anniel@nym.alias.net.invalid>,
A N Niel <anniel@nym.alias.net.invalid> wrote:
Technically, factorial is defined on the integers. I am sure that
he meant Gamma(sin(pi x / 180) + 1).
Rob Johnson <rob@trash.whim.org>
take out the trash before replying
to view any ASCII art, display article in a monospaced font |
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