The Texas Instruments TI-84 is a graphic calculator used for higher-level math. When working out a problem with a TI-84, it is possible that the answer you are looking for is most accurately displayed as a square root. Since a square root can’t be displayed on the calculator, you will need to install the program RADICAL from the TI Program Archive. This way, if you input the square root of 72, “rad(72” the output will be “6* rad(2” or 6 square root of 2.
Download the free TI Connect Software from Texas Instruments (see Resources). This will allow you to download programs and apps onto your TI-84.
Download the RADICAL.8xp program from Texas Instruments Index of programs (see Resources). Click on the link and it will start to download automatically.
Save the program on your desktop.
Connect your TI-84 to a computer using a TI Connect. Your calculator may have come with one of these, but you can also purchase one from Texas Instruments (see Resources).
Load the program onto your TI-84, according to your computer. In Windows, drag and drop the program file onto the icon for TI Connect. In OSX, the TI Device Explorer will pop up when you plug in the calculator. Launch it, and the name of your calculator will come up. Drag and drop the program file onto the calculator name, and the files will transfer.
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When you download the radical program, you may be prompted to update your OS. To do this, you will need to turn on your TI-84, press 2nd MEM, then press ENTER. This will check for the OS.