HP -22S Owner's Manual page 84

Example: Area of a Polygon. The equation for the area of a regular
polygon with
n
sides of length d equals:
Area
=
~ nd
2
cos(1r In)
4 sin(1rln)
The equation is entered into the list of equations as:
Calculate the area of a pentagon with equal sides 6 centimeters long.
Keys: Display:
.1
EQUATIONS
I
Description:
Displays the equation
list.
If necessary, press [!] until the HP-22S displays
TYPE NEW EQN.
Type the equation,
*
then:
N?value
D?value
6
1
INPUT
I
A=4,103.3434
Prompts for N.
Stores N, prompts for
D.
Calculates the area.
• The keystrokes for typing the equation are
1 STO I
A
G
1 STO I
N
01 STO I
0
0
2
01 cos I
.0[±]lsTOI N [D[±][D 4 0IsINI.0[±]lsTOI N [D[D.
1j4 6: Evaluating and Solving Equations