6

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

V = .25 π d2 l

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 ‘ Nz2.5 !z16 zcalculates the volume of 16 inches of 2 1/2–inch 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:

Display:

Description:

H

 !!

Selects Equation mode, shown

 

or the current equation

by the EQN annunciator.

Entering and Evaluating Equations

6–1

Page 93
Image 93
HP 33s Scientific manual Entering and Evaluating Equations, How You Can Use Equations, Example Calculating with an Equation