Entering And Evaluating Equations; How You Can Use Equations - HP 33s User Manual

Entering and Evaluating Equations

How You Can Use Equations

You can use equations on the HP 33s in several ways:
For specifying an equation to evaluate (this chapter).
For specifying an equation to solve for unknown values (chapter 7).
For specifying a function to integrate (chapter 8).
Example: Calculating with an Equation.
Suppose you frequently need to determine the volume of a straight section of pipe.
The equation is
where d is the inside diameter of the pipe, and l is its length.
You could key in the calculation over and over; for example, .25
j ¸ = ¸
2.5
diameter pipe (78.5398 cubic inches). However, by storing the equation , you get
the HP 33s to "remember" the relationship between diameter, length, and
volume — so you can use it many times.
Put the calculator in Equation mode and type in the equation using the following
keystrokes:
Keys:
º d
V = .25
¸
16 calculates the volume of 16 inches of 2
Display:

or the current equation 
Entering and Evaluating Equations
2
d l
Description:
Selects Equation mode, shown
by the EQN annunciator.
6
Ï º
1
/ –inch
2
6–1