HP 50g Graphing Calculator - Manual (Page 164)

Page 3-34
Function TINC
Function TINC(T
0
, ΔT) calculates T
0
+DT. The operation of this function is similar
to that of function TDELTA in the sense that it returns a result in the units of T
0
.
Otherwise, it returns a simple addition of values, e.g.,
Defining and using functions
Users can define their own functions by using the DEF command available
thought the keystroke sequence „à (associated with the 2 key). The
function must be entered in the following format:
Function_name(arguments) = expression_containing_arguments
For example, we could define a simple functionH(x) = ln(x+1) + exp(-x).
Suppose that you have a need to evaluate this function for a number of discrete
values and, therefore, you want to be able to press a single button and get the
result you want without having to type the expression in the right-hand side for
each separate value. In the following example, we assume you have set your
calculator to ALG mode. Enter the following sequence of keystrokes:
„à³~h„Ü~„x™‚Å
‚¹~„x+1™+„¸~„x`
The screen will look like this: