HP 48g Graphing Calculator - Manual (Page 92)

To include units:
1. Key ill the number part.
2. Press fr^fT) to start the unit expression.
3. Key in the unit expression.
4. Press © to end the expression.
You can also build unit objects (described in chapter 10) in the
Equation Writer application. For compound units, press or © to
separate each individual unit in the unit expression. You can key in
unit names in one keystroke by pressing the corresponding menu key
in the UNITS Catalog menu.
To include ! (where) functions:
1. Key in a parenthetic e.xpressioii with symbolic arguments.
2. Press [4^fSYMBOLIC) (NXT) I to display I . The cursor is
positioned at the bottom right of the symbol.
3. Key in the defining equation for each argument, pressing or
OE] to key in =, and dE© to key in the separator between each
equation.
4. Press B to end the function.
The I (where) function substitutes values for names in expressions. It’s
described under ’‘Showing Hidden Variables” on page 20-17.
Controlling Implicit Parentheses
Implicit parentheses are turned on whenever you start the
Equation Writer application. This means the arguments for
and O are normally enclosed in “invisible” parentheses, so that only
(or ®) ends the argument.
If you turn off implicit parentheses, the argument ends when you enter
the next function—or press ©•
To turn implicit parentheses on or off:
■ Press QCI©- A message briefly displays the current state.
Disabling implicit parentheses is convenient for entering polynomials,
for example, where exponents are completed when you enter the
function that starts the next term.
7-6 The EquationWriter