# TI-83 Resources

Click on the TI-83 image to the right to view an Adobe Acrobat file that describes the use of the TI-83 graphing calculator.

If you've lost or mislaid the one that was packaged with your new calculator, you can download a copy of the TI-83 User Guide (another Adobe Acrobat file) that Texas Instruments provides with each new calculator. Click this link and you'll be taken to the Texas Instrument website: TI-83 User Guide.

If you decide to use some other calculator in your work, please be aware that no classroom assistance can be rendered to you, due to time constraints. In other words, you're on your own!

The most important thing to teach you about the calculator is this: You must always be aware that, when entering mathematical expressions into the calculator, it has an “order of operations” which it follows. This simply means that things we humans write on multiple lines (for instance fractions, or exponents) the calculator cannot understand without the help of parentheses. You MUST provide parentheses around expressions that are in the numerator, denominator, or used as exponents, or else you will get incorrect results.

To illustrate, consider this expression:

If you just enter that as 5.9X+8.3/7.5-2X, it won't be the same thing. That's because the calculator first performs multiplication and divisions before going back and performing additions and subtractions.

In other words, what the calculator thinks it says is this:

The way around this is to use parentheses; the calculator will first perform the items within the sets of parentheses. Thus, the expression has to be entered, with parentheses, as (5.9X+8.3)/(7.5-2X) in order to get the right answer.