# I just bought the TI-89 at amazon... **URL:** \ **Category:** In My Humble Opinion\ **Created:** [February 4, 2007, 6:43pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808 "2007-02-04T18:43:25Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [February 4, 2007, 6:43pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/1 "2007-02-04T18:43:25Z")
…to do probabilities, permutations and combinations, and whatever other math is involved in Texas Hold 'em. The TI-83+ was a few bucks more, so I opted for the more powerful 89. Did I make a mistake? Don’t laugh. Oh, okay, laugh, but please post your opinions on the efficacy of the 89 vs the 83+. 😃😃😃 Oh. I’ll be using a book entitled **Killer Poker by the Numbers** by Tony Guerrera. Mr. Guerrera did all his calculations on a TI-83. ---
**Author:** ![Absolute](https://avatars.discourse-cdn.com/v4/letter/a/b2d939/32.png) [@Absolute](https://boards.straightdope.com/u/Absolute)\ **Post date:** [February 4, 2007, 8:19pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/2 "2007-02-04T20:19:48Z")
The TI-89 is great, mostly because of the user interface. It ‘pretty-prints’ the calculations you enter, so that they display on the screen like they would if you had written them on paper, which makes it much easier to verify that you’ve input something correctly. It also makes it very easy to go back and fix an error in your input, reuse the result of a previous computation, and so forth. ---
**Author:** ![quelquechose](https://avatars.discourse-cdn.com/v4/letter/q/6f9a4e/32.png) [@quelquechose](https://boards.straightdope.com/u/quelquechose)\ **Post date:** [February 4, 2007, 9:41pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/3 "2007-02-04T21:41:42Z")
I’ve used both, and I really prefer the TI-89. The main thing that I use it for is solving equations and simplifying expressions when it would be tedious to do so by hand. It’s also nice for computing integrals quickly, and much more reliable than working them out myself. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [February 4, 2007, 9:59pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/4 "2007-02-04T21:59:47Z")
Since there is no General Question here, let’s move this to IMHO. **samclem** GQ moderator ---
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [February 4, 2007, 10:59pm UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/5 "2007-02-04T22:59:54Z")
Thanks Sam, you’re right. ---
**Author:** ![TJdude825](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@TJdude825](https://boards.straightdope.com/u/TJdude825)\ **Post date:** [February 5, 2007, 12:51am UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/6 "2007-02-05T00:51:49Z")
You could probably write a program on either one of those, where you type in what cards you have, what cards are on the table, and what cards you suspect the other players might have, and it’ll tell you your odds. It’d be pretty complicated, but I’m sure someone’s done it already. [ticalc.org](http://ticalc.org) might be a good place to start looking for such a program if you don’t want to tackle writing it yourself. The 83 would work, but the pretty-print mentioned above IS really nice. ---
**Author:** ![Rigamarole](https://avatars.discourse-cdn.com/v4/letter/r/77aa72/32.png) [@Rigamarole](https://boards.straightdope.com/u/Rigamarole)\ **Post date:** [February 5, 2007, 1:31am UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/7 "2007-02-05T01:31:12Z")
The main advantage of the TI-83 is that it is the standard calculator used in most schools (in the US at least), so it’s easier to follow along and get help with it if you are enrolled in math classes using it. If you aren’t in school and haven’t already spent time getting familiar with it, the 89 is probably better (although I admit I’ve only used it briefly) ---
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [February 5, 2007, 2:10am UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/8 "2007-02-05T02:10:23Z")
[QUOTE=Rigamarole] If you aren’t in school and haven’t already spent time getting familiar with it, the 89 is probably better (although I admit I’ve only used it briefly) [/QUOTE] That’s me. From yours and others posts, it looks as if I made a good buy. Thanks, \*\*Rigamarole \*\*and all the rest of you. Oh. **TJ** , I went to [ticalc.org](http://ticalc.org) and they didn’t seem to have what I want. If I run across a program written for a TI-83 84, etc., what are the chances I could download and use it in my TI89? ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [February 5, 2007, 3:10am UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/9 "2007-02-05T03:10:04Z")
Beware if you plan on taking a standardized test with a TI-89: they’re banned from most of the tests out there (SAT for sure, 99.9% positive for the ACT). ---
**Author:** ![Cleophus](https://avatars.discourse-cdn.com/v4/letter/c/a88e57/32.png) [@Cleophus](https://boards.straightdope.com/u/Cleophus)\ **Post date:** [February 5, 2007, 3:19am UTC](https://boards.straightdope.com/t/i-just-bought-the-ti-89-at-amazon/390808/10 "2007-02-05T03:19:11Z")
[QUOTE=John DiFool] Beware if you plan on taking a standardized test with a TI-89: they’re banned from most of the tests out there (SAT for sure, 99.9% positive for the ACT). [/QUOTE] Not so. The SAT’s [calculator policy](http://www.collegeboard.com/student/testing/sat/testday/calc.html) bans calculators with keyboards, calculators that exist as software on another device (PDA, etc.), and calculators that must be plugged in, make noise, or use paper tape. The TI-89 has none of those features. TI’s product page even mentions that the 89 is permitted for the SAT and other tests. The TI-92, though, has a keyboard. Were you thinking of that? That said, the TI-89’s extra features over, say, the TI-83 probably won’t help you on the SAT.