Cosecant, cotangent, secant...
iOLO
hey, why is there no builtins for Secant, Cosecant, and Cotangent?
like to use for differentiation in Calculus? is there a program that
will do that?
>>>>-----iOLO----->
Stefan Berglund
In article <32e94643...@nnrp.crl.com>, sad...@crl.com (iOLO) writes:
> hey, why is there no builtins for Secant, Cosecant, and Cotangent?
Why? Because they aren't of any real use.
> like to use for differentiation in Calculus? is there a program that
> will do that?
Yes, and HP was kind enough to include it right on the keyboard and labeled
it 1/x
--
/Stefan
f94...@dd.chalmers.se
Life - the ultimate practical joke
Andre Schoorl
In article <32e94643...@nnrp.crl.com>, iOLO wrote:
>hey, why is there no builtins for Secant, Cosecant, and Cotangent?
>will do that?
Because they're all just inverses of the normal trig. functions.
--
Andre Schoorl <asch...@engr.uvic.ca> PGP key available via finger/keyserver
C.Eng Student, U.Vic, Canada. - Linux/HP48 - http://www.engr.uvic.ca/~aschoorl
Ezequiel Pitton
sad...@crl.com (iOLO) wrote:
>hey, why is there no builtins for Secant, Cosecant, and Cotangent?
>like to use for differentiation in Calculus? is there a program that
>will do that?
>>>>>-----iOLO----->
Maybe because pressing INV is easier.
E. Pitton
Robb
: hey, why is there no builtins for Secant, Cosecant, and Cotangent?
: like to use for differentiation in Calculus? is there a program that
: will do that?
I havent got my HP48 yet, but on my old Radio Shack calc, you just hit
inverse and the regular trig functions.
1/sin = csc
1/cos = sec
1/tan = cot
Im not sure about the graphing thing.. like I said, i aint got the calc
yet.
Robb
Eric Gorka
If you REALLY want to have those functions built in, get a SPARCOM
Mathematics Pack... It will take you MANY more keystrokes than a 1/x button
push though...
Robb <ro...@sky.net> wrote in article <5cblvi$6...@alpha.sky.net>...
John H Meyers
In article <32e94643...@nnrp.crl.com>, sad...@crl.com writes:
> Why are there no built-ins for Secant, Cosecant, and Cotangent?
Have you seen these functions built into any calculator?
The HP48 allows you to create any functions you desire, to augment the
built-in function set, and allows you to define their derivatives as well!
To define SEC(x) in terms of built-in functions:
'SEC(x)=INV(COS(x))' DEFINE
To use the above definition:
'SEC(60)' DEG EVAL --> 2
'SEC(X)' 'X' RAD [derivative] --> 'SIN(X)/COS(X)^2'
> Like to use for differentiation in Calculus?
To define only the derivative of SEC(x):
'derSEC(x,dx)=SEC(x)*TAN(x)*dx' DEFINE
(Be sure to spell exactly as shown, with lower-case letters "der")
To use the above definition:
'SEC(X^2)' 'X' [derivative] --> 'SEC(X^2)*TAN(X^2)*(2*X)'
(note that the current angle mode has no effect, because our
own definition of the derivative did not take it into account)
If you define *both* functions SEC(x) and derSEC(x),
the HP48 will differentiate your function SEC(x) directly,
ignoring your redundant definition of derSEC(x).
Yes, this is covered in Chapters 11 and 20 of the G/GX User's Guide!
-----------------------------------------------------------
With best wishes from: John H Meyers ( jhme...@mum.edu )
Boyscout
iOLO wrote:
>
> hey, why is there no builtins for Secant, Cosecant, and Cotangent?
> like to use for differentiation in Calculus? is there a program that
> will do that?
If I'm not wrong, you can do them by taking the inverse of the (angle,
number, whatever you want to call it) and using the Acos Asin and Acot
functions.
Joeri Van hoyweghen
Sorry, I guess you're wrong
CoTan a = 1 / Tan a = Cos a / Sin a <> aTan (1/a) !
Sec a = 1 / Cos a ) (Don't shoot me if it's Sin here and Cos below)
CoSec a = 1 / Sin a (but who(m?) uses Sec and Cosec anyway)
Joeri
Joeri Van hoyweghen
Joeri
Danny Bersch
In article <32F159...@3rivers.net>, Boyscout <dil...@3rivers.net> writes:
#]iOLO wrote:
#]>
#]> hey, why is there no builtins for Secant, Cosecant, and Cotangent?
#]> like to use for differentiation in Calculus? is there a program that
#]> will do that?
#]> >>>>-----iOLO----->
#]If I'm not wrong, you can do them by taking the inverse of the (angle,
#]number, whatever you want to call it) and using the Acos Asin and Acot
#]functions.
Ah, but if you *are* wrong, you may discover that, by definition,
Cosecant = 1/sin, Secant = 1/cos, Cotangent = 1/tan
Basics, my boy, basics. One might even take the John Meyers' approach
and assign these to keys
[CSC] [SEC] [COT]
<< SIN 1/X >> << COS 1/X >> << TAN 1/X >>
This won't actually help you if you are trying to use symbolics, but it
will make John feel better because it is a programming *solution*.
(Just in fun, John; just in fun.)
--
========================================================================
Danny Bersch | There is only one basic human right, the right
Motorola | to do as you damn well please. And with it
SPS, LATG, ATO, SST | comes the only basic human duty, the duty to
ber...@sst.sps.mot.com | take the consequences. -P.J. O'Rourke
========================================================================
Dick Smith
In message <32F159...@3rivers.net> Boyscout wrote:
] iOLO wrote:
] >
] > hey, why is there no builtins for Secant, Cosecant, and Cotangent?
] > like to use for differentiation in Calculus? is there a program that
] > will do that?
] > >>>>-----iOLO----->
] If I'm not wrong, you can do them by taking the inverse of the (angle,
] number, whatever you want to call it) and using the Acos Asin and Acot
] functions.
Sorry, but this is wrong. These are the reciprocals of sin, cos and tan
So Secant = 1/cosine
Cosecant = 1/sine
Cotangent = 1/tan
That's why no calculator has buttons for 'em---they're not needed.
Cheers
Dick
--
=============================================================================
Dick Smith Acorn Risc PC di...@risctex.demon.co.uk
=============================================================================
AceTracer
Joeri Van hoyweghen wrote:
>
> Boyscout wrote:
> >
> > iOLO wrote:
> > >
> > > hey, why is there no builtins for Secant, Cosecant, and Cotangent?
> > > like to use for differentiation in Calculus? is there a program that
> > > will do that?
> > > >>>>-----iOLO----->
> > If I'm not wrong, you can do them by taking the inverse of the (angle,
> > number, whatever you want to call it) and using the Acos Asin and Acot
> > functions.
>
>
> CoTan a = 1 / Tan a = Cos a / Sin a <> aTan (1/a) !
> Sec a = 1 / Cos a ) (Don't shoot me if it's Sin here and Cos below)
>
> Joeri
Actually, csc, sec, and cot are used quite a bit. Ever heard of
Trigonometric Identities? Basic trig in my high school, and used in many
different fields. I myself was annoyed at having to punch in 1/sin
anytime I wanted the csc of an angle, especially if used in a large
equation that already takes enough of my G's screen. Not very good
symbolically either, makes me look twice when I look at an equation
saved a while ago.
I found that I have yet another reason to curse the HP38. It does have
cot, csc, and sec built-in to it's OS, though I don't think it has an
Equation Writer so it's really irrevelant. This adds to the list of
features I found built-in to the 38, but not the 48. Others include a
notepad and writing text in PICTURE.
Andy
Matthew Mastracci
On Fri, 31 Jan 1997, Joeri Van hoyweghen wrote:
Uhh? Your reasoning is quite wrong. Follow mine:
> CoTan a = 1 / Tan a = Cos a / Sin a <> aTan (1/a) !
/
C / |
/ | A a, b and c are angles opposite of sides A, B and C.
/___|
B
tan a = opp/adj = A / B
cot a = 1/tan = adj/opp = B / A
Now:
a = arctan (A / B), right?
Let's set x = B / A, so cot a = x
Now, a = arccot x = arccot B / A
Therefore,
arctan (A / B) = arccot (B / A)
and,
arctan (1 / x) = arccot x
> Sec a = 1 / Cos a ) (Don't shoot me if it's Sin here and Cos below)
> CoSec a = 1 / Sin a (but who(m?) uses Sec and Cosec anyway
Try the same for the others.
You may wish to brush up on your trig,
/\/\att /\/\astracci mmas...@acs.ucalgary.ca
GCS/GE d- s+:+ a--- C++++ UA P+ L E-- W+ N++ o K+ w+ O M- V
PS++ PE++ Y+ PGP t+++ 5+++ X++ R++ tv+ b+++ DI++++ I
G++ e h r* z?
Paul Schlyter
In article <32F206...@minf.vub.ac.be>,
Ver a = 1 + cos a
Cover a = 1 + sin a
Hav a = ( 1 + cos a ) / 2
Exsec a = Sec a - 1
Those obsolete trig functions are fun! :-)
--
----------------------------------------------------------------
Paul Schlyter, Swedish Amateur Astronomer's Society (SAAF)
Grev Turegatan 40, S-114 38 Stockholm, SWEDEN
e-mail: pau...@saaf.se p...@net.ausys.se pa...@inorbit.com
WWW: http://www.raditex.se/~pausch/ http://spitfire.ausys.se/psr/
Dick Smith
In message <5cvfvr$c...@electra.saaf.se> Paul Schlyter wrote:
] And don't forget:
]
] Ver a = 1 + cos a
] Cover a = 1 + sin a
] Hav a = ( 1 + cos a ) / 2
] Exsec a = Sec a - 1
Yesh, welll, (hic!) I don't know about thoshe, but what abaht sinh, cosh
and tanh, eh!!
rafaelsalaz...@gmail.com
> : hey, why is there no builtins for Secant, Cosecant, and Cotangent?
> : like to use for differentiation in Calculus? is there a program that
> : will do that?
>
> inverse and the regular trig functions.
> 1/sin = csc
> 1/cos = sec
> 1/tan = cot
>
> Im not sure about the graphing thing.. like I said, i aint got the calc
> yet.
>
> Robb