Ti-84 Plus Graphing Calculator For Dummies, 2nd Edition

Chapter 25

Ten Common Errors

In This Chapter

Incorrectly negating numbers

Improperly indicating the order of operations

Forgetting you’re in Radian mode

Accidentally deleting a list or a function

Even the best calculating machine is only as good as its input. This chapter identifies ten common errors made when using the calculator. Wouldn’t it be great to avoid some of the common errors that normally plague students who are using calculators?

Using - Instead of _ to Indicate That a Number Is Negative

If you press - instead of _ at the beginning of an entry, the calculator assumes you want to subtract what comes after the minus sign from the previous answer. If you use - instead of _ in the interior of an expression to denote a negative number, the calculator responds with the ERROR: SYNTAX error message.

Indicating the Order of Operations Incorrectly by Using Parentheses

When evaluating expressions, the order of operations is crucial. To the calculator, for example, –32 equals –9. This may come as quite a surprise to someone expecting to square –3, where (–3)2 equals 9. The calculator ...