HP 40G manual Scientific notation powers, Explicit and implicit multiplication

Scientific notation (powers of 10)

Example

Explicit and implicit multiplication

H I N T

A number like 5 ⋅ 104 or 3.21 ⋅ 10– 7 is written in scientific notation, that is, in terms of powers of ten. This is simpler to work with than 50000 or 0.000000321. To enter numbers like these, use EEX. (This is easier than using >;@10>[N@.)

(4 ⋅ 10– 13 )(6 ⋅ 1023 ) Calculate ----------------------------------------------------

3⋅ 10– 5

>￿@￿4 >6+,)7@EEX

>￿￿￿@13￿>￿@

>;@￿>￿@6 >6+,)7@EEX

23>￿@ >j@ 3 >6+,)7@EEX

>￿￿￿@5

>(17(5@

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.

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.

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