HP 32SII User Manual

Page 118

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7–8 Solving

Equations

File name 32sii-Manual-E-0424
Printed Date : 2003/4/24 Size : 17.7 x 25.2 cm

to enter guesses before solving for T because in the first part of that
example you stored a value for T and solved for D. The value that was left
in T was a good (realistic) one, so it was used as a guess when solving
for T

.

If an equation does not allow certain values for the unknown, guesses

can prevent these values from occurring. For example,

y = t + log x

results in an error if x

0 (messages

1 2

or

12

).

In the following example, the equation has more than one root, but guesses
help find the desired root.

Example.

Using Guesses to Find a Root.

Using a rectangular piece of sheet metal 40 cm by 80 cm, form an open–top
box having a volume of 7500 cm

3

. You need to find the height of the box

(that is, the amount to be folded up along each of the four sides) that gives the
specified volume. A taller box is preferred to a shorter one.

40

80

40_2

H

H

H

80_2

H

H

H

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