Appendix C: The Hp 40G & Its Cas; Introduction; What Is A Cas - HP 39g Master Manual

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P P E N D I X
P P E N D I X
I n t r o d u c t i o n
I n t r o d u c t i o n
This appendix is intended to give a useful introduction and over view to the
user who is new to an hp 40g. It is not intended to fully cover the topic, nor is
it intended to serve as a reference text for the advanced user. For those
needing a far more extensive coverage than is available here, I can highly
recommend the incredibly detailed text "Computer Algebra and Mathematics
with the hp 40g, Version 1.0" by Renée de Graeve, Lecturer at the University
of Grenoble I and founder of the Grenoble IREM. It contains a complete
reference of the functions for symbolic calculation, and also demonstrates,
using many examples, how to take smart advantage of the calculating power
of the hp 40g. This can be found at Hewlett Packard's web site
(http://www.hp.com/calculators) or on the Help page of The HP HOME view
(http://www.hphomeview.com).

What is a CAS?

Although you may not have thought about it consciously, you are probably
aware that most calculators do not operate with algebra in the same way that
a human does. Generally speaking solutions on computers and calculators
are found using numeric means. This is often done by using successive
approximations, each one coming closer and closer to the final answer.
You can see this process at work quite easily using the Solve aplet. All you
need to do is enter an equation to solve which is complex enough to require
more than a few seconds to solve. If you do this then you can watch the
calculator work.
In the Solve aplet, enter the equation
2
(0, X, A , X) = 1000 as shown right.
This is equivalent to solving for a in the
∫ x
a dx =
equation:
2
0
Change into the NUM view, and press
X. As soon as the hour glass symbol appears,
press the button again. You may need
to press it more than once before the
calculator takes notice, but eventually you
should see a view similar to the one right.
C : T 4 0
C : T 4
H E H P
H E H P
.
1000
& C A S
0 & C A S
G I T S
G I T S
on
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