Page 3 is especially enlightening as to why the user should read the owners manual when using a calculator.
Example 6, in particular, shows that there's two kinds of people in this world, TI-85 (old) and TI-86 (young). Whereas they show the results of TI-86 to be "as expected", I would have expected the results of TI-85 myself. Guess I'm getting old!
:-)