My ti-84 plus it does not respond to the function + or - OR other function, & it come up to display very slow ,slow. thanks

Is it somehow preventing you from graphing, or are you simply not getting the graph you expect?

Most likely you have the angular mode set wrong. You probably want it set to radians. Press MODE, move to the third line, highlight RADIAN, press ENTER, then 2ND [QUIT].

If it's not the angular mode, please reply to this post and give an example or two.

The INV key that you may find on some scientific calculators has, on the TI 83/84/ Plus calculators, an equivalent key marked [2nd].

On the TI83/84 Plus, each trigonometric function has a second marking [SIN^-1], [COS^-1] or [TAN^-1]. To calculate the inverses of trigonometric functions ( arc sine, arc cosine, arc tangent) you press [2nd] followed by the relevant trigonometric function key For example, [2nd] [SIN] displays sin^-1( on the command line.

Unfortunately the hyperbolic functions and their inverses are only accessed through the CATALOG. You press [2nd][0] to open the CATALOG. Then you scroll down the CATALOG list to reach cosh(, cosh^-(, sinh(, sinh^-1(, tanh(, or tanh^-1(.
To speed the search in the catalog, you use the ALPHA keyboard: To reach cosh(, press[PRGM] and you scroll down from there.

Here is for you. From the TI Knowledge base.
Why does my TI-84 Plus or TI-89 Titanium respond slowly to key press entries?

Issue/Symptom: When making key press entries, the product responds slowly

If a piece foreign material such as a pencil lead is lodged in the I/O port of the calculator, it may create a short causing the calculator to respond slowly to key press entries.

If the piece of conductive material can be removed, it may restore the calculator to normal operating condition.

If the material cannot be removed, contact TI-Cares Customer Support to proceed with an out of warranty product replacement.

If conductive material is not lodged in the I/O port and the calculator responds slowly to key press entries, contact TI-Cares Customer Support for further troubleshooting and resolution.

That is simple. It is a function like any other.
Press the key marked [SIN]
Screen displays sin(
Enter the value of the angle (make sure the current angle unit is the appropriate one).
Close the right parenthesis and press [ENTER]

Hi yeager anna,

Since the calculator operates slowly even after the RAM has been cleared, I'd say, "Your OS must be corrupt." You need to re-install the Ti 84 Plus OS, ASAP!!! You can fix this problem by installing the newest Ti 84 Plus 2.55v. MP OS, operating system. Use fresh batteries when installing the new OS. If you need additional instructions your welcome to read my Ti 84 Plus solutions. I pretty much tell how you can install the new OS with another Ti 84 Plus calculator or, connecting the computer to the calculator to install the new OS. You can view my solution to install OS by clicking, "Ti 84 Plus OS installation." Just stroll down to oneplusgh's solution at that posting and, I cover a lot of topics you may need advice on to install the new OS.

If you need instructions to downloading and installing TI Connect on a XP or, Mac computer click, "TI Connect on a XP or Mac computer." I realize this posting was for a later OS but, this link will take you to the latest TI Connect software and, newest OS too. Once you get the TI Connect software installed come back to this posting and, follow the instructions above at "Ti 84 Plus OS installation."

If you need instructions to downloading and installing TI Connect on a Windows 7 computer click, "TI Connect on a Windows 7 computer." Just follow Procedure 3. You can also get instructions at this link on how to install the Ti driver to link computer and calculator. I realize this link instructions were for a Ti 89 calculator but, they will work for a Ti 84 Plus too. Once you get the TI Connect software installed come back to this posting and, follow the instructions above at "Ti 84 Plus OS installation."

My instructions is geared to save you a lot of hardship. No matter if your having to install Ti Connect or, the newest OS for your calculator. I do not use TI OSDownloader because, TI OSDownloader might not give you the newest OS for your calculator. My instructions will. If you have any questions just post a comment and, I'll respond quickly.

Hi purzabumafu8,

You need to re-install the Ti 84 Plus OS on both calculators, ASAP!!! You can fix these problems by installing the newest Ti 84 Plus 2.55v. MP OS, operating system. Use fresh batteries.

If you have a friend that has a Ti 84 Plus or, Ti 84 Plus Silver Edition you can connect the two calculators together through the USB or, IO link ports. Then they can send you a copy of their OS, while you receive it on your Ti 84 Plus. Hopefully, your friend will have Ti84 Plus 2.55v. MP OS on their calculator or, it might not work. Link the two calculator together through the USB or, IO link ports with the proper cable. If don't have another reliable calculator to connect too, you'll have to connect the calculator to a computer to download the OS, goto Procedure 5. If your downloading off another calculator goto Procedure 1.

Important Note: Never disconnect a TI Connectivity Cable during a transfer. Lost of power during installation of OS will destroy your calculator.

Procedure1. Procedure to linking to another calculator.
On their calculator press, [2nd][Link][G] [Right-Arrow]. On your calculator press, [2nd] [Link] [Right-Arrow] [Enter] and, then press [ENTER] on their calculator too. Their calculator should say, "TRANSMIT" and, your's will say "Receiving." Then on both calculators once transfer is complete press, [2nd][MODE] to quit and, return to the Home screen. If the OS was transferred then your finished with these procedures. If your calculator won't turn on or, is locked up try the Procedure 2, below.

Procedure 2.

Remove one of the AAA batteries. Press and hold the [DEL] key. While holding [DEL], reinsert the AAA battery and then turn the calculator on. The calculator should display
"Waiting...Please install calculator software now". If calculator did not turn on or, is still locked up goto Procedure 3, unless already did Procedure 3, then goto Procedure 4. If you calculator does come on and is responding and, your connect to another calculator goto Procedure 1. If you calculator does come on and is responding and, your connect to a computer goto Procedure 7.

Procedure 3.

Remove all of the batteries including the round lithium battery for 5 minutes. After the 5 minute period, reinsert all of the batteries and turn the calculator on. Adjust the contrast if necessary. Goto Procedure 2.

Procedure 4.

If the above process did not work. Try re-doing the Procedure 2, and, this time extend the time in Procedure 3, by 5 minutes to 10 minutes before you put all the batteries back in the calculator. These calculators can be a little stubborn at times so, keep trying Procedure 2.

Procedure 5.

If you can't find a calculator to connect too, you can connect your Ti 84 Plus to a computer that has Ti Connect software on it. If you need to connect your Ti 84 Plus to a computer make sure the Ti Connect software is operating properly. You do not want any hang-ups while installing the Ti 84 Plus OS.
Procedure 6. Procedure to installing the latest Ti84 Plus 2.55v. MP OS. TI OSDownloader does not always install the latest OS.
You can get the latest copy of Ti84 Plus 2.55v. MP OS and, guidebook by going to the Texas Instruments web site. You can get to that site instantly by clicking, "Ti 84 Plus 2.55v. MP OS!" Once your at the Ti site click the Download Item, "Ti84 Plus family operating system". Next you can login or, click "continue as guest". I'd would click the "continue as guest". Once you have click, "continue as guest" the Ti84 Plus family operating system will download to you.
Next, click "SAVE" and then a window to a folder will pop up. It is probably a window to a folder that you download too. If so, you may want to change it and, save to this folder, "My Documents \ My TI Data \ Downloads". You can also go back and, download the Ti 84 Plus guidebook too, if needed. If your calculator will not turn on or, is locked up goto Procedure 2. Or else goto Procedure 7.

Procedure 7.
Important Note: Never disconnect a TI Connectivity Cable during a transfer. Lost of power during installation of OS will destroy your calculator.
Link your computer and, Ti 84 Plus calculator with the USB cable or, Direct Black Link cable that came with the Ti 84 Plus calculator. Next, drag the Ti 84 Plus 2.55v MP OS that you saved earlier in "My Documents \ My TI Data \ Downloads" out of that folder and, drop it in the "Ti Connect" icon on the desktop. Click, "Continue" when the "Erase Warning" pops up and, the new Ti 84 Plus 2.55v MP OS will begin to install. Next, the Ti Device window should pop up and, highlight the port when it finds what your Ti 84 Plus is using, USB1 cable or, Direct Black COM1.

When the Ti Device Explorer finds and, highlights your calculator's information click, "Select." Then click, "Yes" when the next window shows up with your calculator's information and, the OS will continue to download. Upon completion the newest Ti 84 Plus 2.55v. MP OS will be installed.
If you run into any trouble with software or, drivers just comment to what failed at this posting and, I'll be glad to help you.

what helped for me is leaving it w/h any battery's (no backup battery either) for a few days. Now miraculously it works!

In order to select additional graphs, the Transformation Graphing Application will need to be uninstalled from the TI-83 Plus Family and TI-84 Plus Family.

More information regarding this matter can be found in the Knowledge Base. The Knowledge Base can be accessed by clicking on the URL below:

http://epsstore.ti.com/OA_HTML/csksxvm.jsp?nSetId=65121&nUsePub=NO&jttst0=6_23871,23871,-1,0,&jtfm0=&etfm1=&jfn=ZG14E1108A3A0CD3ABADCD67260B59BDE0CEEA20790F80F708D8A4FDACCD82D31F792BC1B01D2F67ECAE6718104B82CC1C8F

Hi,
You cannot use the ± in the definition of a function. If you need to consider two alternatives, you have draw each function separately, one function as Y1 and the other as Y2. I just checked the catalog of commands, and there is no ±.

Hope it helps.
Thanks for using FixYa

might want to reinstal program and APP's. Check memory size too. You might free up some memory