HP -28S Manual page 81

For example, you can define a function COT for the cotangent func-
tion, where cot x
=
1/tan x.
Begin the program.
o
Indicate the argument .
• G
[ill
x
[ill
2: 0
1: 2.46855006079
«I
CIBImJIII:lI3IDD1G1l1m1IDI:l11
2: 0
1: 2.46855006079
«
~
xl
CIBImJIII:lI3IDD1G1l1m1IDI:l11
The right arrow indicates that the following name represents a
local
variable,
which will exist only within this program.
It's useful to follow some convention to distinguish your local vari-
ables from your ordinary or Hglobal H variables. This manual uses
lower-case letters to distinguish local variables. (Pressing [ill once
switches to lower case; pressing [ill a second time switches back to
upper case.)
Define the function.
CJ
.OEJ
CO
TAN
CO
I
LC
I
x
Enter the program.
I
ENTER
I
2: 0
1: 2.46855006079
«
~
x'
INV (TAN(xl
CIBImJIII:lI3IDD1G1l1m1IDI:l11
2: 2.46855006079
1: «
~
x
'INV(TAN(x»'
»
CIBImJIII:lI3IDD1G1l1m1IDI:l11
The closing parentheses and delimiters are added for you.
80 5: Real-Number Functions