Thread: TI-89 help

Can someone tell me how to find the following on the T1-89(titanium) calculator: (in this way please, for example the first derivative is d(f(x),x)).): a derivative implicitly, an nth derivative, limits (one sided and full), and can u tell me if it's possible to make the ti give me decimals? i hate carrying around an 89 for calc and 84 for statistics. Thanks alot.

All of this is in the manual or online.


For implicit diff, look for ImpDif under the calc menu.

For a second derivative, after the x,type the number corresponding to the nth derivative.

example: will give the second derivative. Just enter 3,4,5, etc for any other derivatives.

For one-sided limits, if you want right, enter in 1. For left, enter -1.

example: left-sided limit, approaching 0 from the left:


And of course it'll give decimals. Set it to 'approx' mode or just press the green key and then enter.
Look above your ENTER button. Is there a squiggly looking equal sign?. That means approximate.

Originally Posted by jarny

and can u tell me if it's possible to make the ti give me decimals?

Another easy way to make the 89 give you decimals is type a decimal into any of the numbers you type in. For example if you type 1/4 it will give you 1/4, if you type 1./4 it will give you 0.25. This is of course a temporary solution, but better if you want decimals only sometimes.

Originally Posted by jabroni1212

Another easy way to make the 89 give you decimals is type a decimal into any of the numbers you type in. For example if you type 1/4 it will give you 1/4, if you type 1./4 it will give you 0.25. This is of course a temporary solution, but better if you want decimals only sometimes.

You can set the dec setting in "MODE" under "Exact/Approx"
The three options there are:
Auto - Will return the answer depending on the format you entered.
Exact - Will give answers in fractions
Approx - Will always return a dec

PS. To make the TI return a dec, Hit <> (Diamond) + ENTER. Instead of just Enter!

that if you push the yellow button with the black triangle in it before you push enter it gives you a decimal...this is true for the Titanium edition