HP (Hewlett-Packard) F2215AA#ABA Calculator User Manual


 
Solving Equations 7-11
It seems reasonable that either a tall, narrow box or a short, flat box could be
formed having the desired volume. Because the taller box is preferred, larger initial
estimates of the height are reasonable. However, heights greater than 20 cm are
not physically possible because the metal sheet is only 40 cm wide. Initial estimates
of 10 and 20 cm are therefore appropriate.
Now check the quality of this solution — that is, whether it returned an exact root —
by looking at the value of the previous estimate of the root (in the Y–register) and the
value of the equation at the root (in the Z–register).
4
H Õ
_
H
_

Terminates and displays the
equation.



Checksum and length.
Keys: Display: Description:
Leaves Equation mode.
H

_
Stores lower and upper limit
guesses.

Displays current equation.
H

value
Solves for H; prompts for V.



Stores 7500 in V; solves for H.
Keys: Display: Description:

This value from the Y–register is
the estimate made just prior to the
final result. Since it is the same as
the solution, the solution is an
exact root.

This value from the Z–register
shows the equation equals zero at
the root.