HP (Hewlett-Packard) HP 17bII+ Calculator User Manual


 
12: The Equation Solver 181
File name : 17BII-Plus-Manual-E-PRINT-030709 Print data : 2003/7/11
Entering Guesses
Entering your own guesses serves two purposes. First, it can save time
by telling the Solver where to start searching. Second, if more than one
solution exists, entering guesses may lead the Solver to a solution in a
specified range. The closer your guesses are to the desired solution, the
better chance the Solver has of finding it.
You can enter guesses at these times:
! Before beginning the calculation, after you’ve stored a value for every
variable except the unknown variable. If you enter one guess, the
Solver generates a second guess.
! After you’ve halted the iterative search.
! After the Solver has returned an answer, and you wish to begin
searching for another answer.
You can enter one or two guesses. If you enter one guess, the Solver
makes a second guess. If you enter two guesses, the Solver uses those
two guesses to start searching for a solution. The Solver works most
efficiently when the answer is between your two guesses. For example,
if you know the answer is between 5 and 12, you should enter 5 and
12 as the starting guesses.
To enter one guess, key in the value and press the menu key twice.
For example, 4.5
- -
enters 4.5 as a guess for a Solver
variable named A and starts the calculation.
To enter two guesses, key in the first guess and press the menu key. Then
key in the second guess and press the menu key twice. For example, 0
-
100
- -
causes the Solver to search for A using 0
and 100.
Example: Using Guesses to Find a Solution Iteratively. One equation
for calculating the profit from a manufacturing operation is: