Evaluating And Solving Equations An Example - HP -22S Owner's Manual

Evaluating and Solving
Equations
An Example
6
1 EVAL I
and
1 SOLVE I
allow you to do calculations involving variables.
For example, suppose you frequently need to determine the volume of
a straight section of pipe. The equation is:
V
=
.25 'If'd
2
1
where d is the inside diameter of the pipe, and I is its length. You
could key in the calculation over and over; for example, .25
0
.@
o
2.5
.~016
calculates the volume of 16 inches of 21f2-inch pipe.
However, storing the equation saves keystrokes and lets you use the
calculator to '"remember' the relationship between diameter, length,
and volume.
Keys: Display:
.1
EQUATIONS
I
Description:
Displays the list of
equations.
If necessary, press [!] until the HP-22S displays
TYPE NEW EQN.
Then:
ISTOI V
G
.250.@0
1
STO I D
[Z)
2
V=
V=.25xtrx
V=.25XtrXOA2
70 6: Evaluating and Solving Equations
1 STO I
V
types
V.
.@
types
tr.
[Z) types ".