HP 39g+ Graphing Calculator User's Guide download pdf (Page 31)

Getting started 1-21

Explicit and

implicit

multiplication

Implied multiplication takes place when two operands

appear with no operator in between. If you enter AB, for

example, the result is A*B.

However, for clarity, it is better to include the

multiplication sign where you expect multiplication in an

expression. It is clearest to enter AB as A*B.

HINT

Implied multiplication will not always work as expected.

For example, entering A(B+4) will not give A*(B+4).

Instead an error message is displayed: “Invalid User

Function”. This is because the calculator interprets

A(B+4) as meaning ‘evaluate function A at the value

B+4’, and function A does not exist. When in doubt, insert

the * sign manually.

Parentheses You need to use parentheses to enclose arguments for

functions, such as SIN(45). You can omit the final

parenthesis at the end of an edit line. The calculator

inserts it automatically.

Parentheses are also important in specifying the order of

operation. Without parentheses, the hp 39g+ calculates

according to the order of algebraic precedence (the next

topic). Following are some examples using parentheses.

Entering... Calculates...

45 π sin (45 + π)

45 π sin (45) + π

85 9

85 9×

1 2 ... 26 27 28 29 30 31 32 33 34 35 36 ... 293 294

No comments

HP 39g+ Graphing Calculator User's Guide Page 31