Re: precision on all calcs
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Re: precision on all calcs
When I subtracted 180*sin(1) from PI, the result was 0.0001594948787 on my
TI-85. This is a difference in the ten-thousandths place. What I was saying in
the message was that _mathematically_, 180*sin(1) does not equal PI; another
person thought that it did and I was pointing that out. The TI-92 does give
answers in terms of PI if an expression mathematically evaluates to PI. Try
entering cos^-1(0) (that's 2nd-COS), and the answer will be PI/2. In fact, the
TI Explorer Plus, a scientific calculator, also treats PI symbolically.
________________
Jeff Tyrrill
http://tyrrill-ticalc.home.ml.org/
http://ti-files.home.ml.org/
-----Original Message-----
From: Scott Trimmer
Sent: Friday, June 27, 1997 7:54 PM
To: Jeff Tyrrill
Cc: CALC-TI@LISTS.PPP.TI.COM
Subject: Re: precision on all calcs
The reason the answer differs is because of the way the TI-92 does sin.
It doesn't do sin exactly. If it did, we could have pi exactly, and we
don't have it quite yet. If you are interested in pi to 1 million places,
search the internet for Project Gutenberg. Also, how did you know where
it differs? Is there some way you can determine that on the 92?
-Scott
=;)
On Sat, 21 Jun 1997, Jeff Tyrrill wrote:
> I just realized something. Even in degree mode, 180*sin(1) does not exactly
> equal pi. It differs in the ten-thousandth place, and if it were pi, the
TI-92
> would give that as an answer, but it doesn't. Oh well. I'll bet changing to
> degree mode solves his problem anyway.
> ________________
>
> Jeff Tyrrill's TI Calculator Site: Contains programming tips, undocumented
> discoveries and tips for power users, and comparisons of the different
> calculator models.
> http://tyrrill-ticalc.home.ml.org/
>
> TI-Files member: The premiere TI site on the web, with reviews of games and
> more.
> http://ti-files.home.ml.org/
>
>
> -----Original Message-----
> From: Jeff Tyrrill [SMTP:jeff_tyrrill@geocities.com]
> Sent: Saturday, June 21, 1997 4:51 PM
> To: CALC-TI@LISTS.PPP.TI.COM
> Subject: RE: precision on all calcs
>
> Change your calculator from the default radian mode to degree mode.
> ________________
>
> Jeff Tyrrill's TI Calculator Site: Contains programming tips, undocumented
> discoveries and tips for power users, and comparisons of the different
> calculator models.
> http://tyrrill-ticalc.home.ml.org/
>
> TI-Files member: The premiere TI site on the web, with reviews of games and
> more.
> http://ti-files.home.ml.org/
>
>
> -----Original Message-----
> From: Open discussion of TI Graphing Calculators On Behalf Of Boogeyman
> Sent: Saturday, June 21, 1997 1:12 PM
> To: CALC-TI@LISTS.PPP.TI.COM
> Subject: precision on all calcs
>
> When I make 180*sin1 on any of my calcs (80,82,92) I got something weird,
> but never pi. Does anybody know if it's the case with other calcs (I only
> go Ti's) ? (It also works with win calc, so I suppose somethin's wrong in
> all the OS.)
>
> TIA
>
> Boogeyman
>