HP 33s Scientific manual 40 , H , Zl H

Type in the equation:

Keys:	Display:	Description:
H		Selects Equation mode
LV d	#/¾	and starts the
		equation.
]40 	
LH `	#/1.2¾
z]20 LH 
`	1.2º1.2¾
z4 zLH	2º1.2ºº¾
‘	#/1.2º1.	Terminates and
		displays the equation.
	/	Checksum and length.
	/

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.

Keys:Display:Description:

‡	
10 IH	
20	_
H	#/1.2º1.
H	#@
	value
7500 g	/
	)

Leaves Equation mode. Stores lower and upper limit guesses.

Displays current equation. Solves for H; prompts for V.

Stores 7500 in V; solves for H.

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).

Solving Equations 7–9