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### HP-38G Graphic Calculator

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Date: 08/29/98 at 11:36:52
From: Mr.R
Subject: Graphic calculator hp38g

I just bought an HP-38G. I've tried to graph some math problems, and
they just won't graph. Mqybe you know about the HP-38G and can help
me. I was trying to graph F(x) = 3x+2 or y = 4x+3.
```

```
Date: 10/22/98 at 13:53:46
From: Doctor Andrewg
Subject: Re: Graphic calculator hp38g

Hi Mr. R!

The HP-38G is a pretty amazing calculator, and graphing functions is a
good way of understanding them. When you do calculus problems this can
be really useful for checking derivatives (slopes), integrals (the
area under the curve), and unusual parts of the graph.

If you follow these steps carefully, you will be able to draw these
graphs.

I assume that you start in the HOME mode. This is where you normally
do your calculations. If you are not already there then press the
"HOME" button (you may need to press "OK" or "CANCEL" first if you are

Now the graphing aplet is a library aplet (it's built in) - so press
"LIB" and a screen with a list of six aplets should appear. The order
that these appear in depends on which ones you used last (the HP-38G
puts those ones at the top to make life easier for you in case you need
them again). One of these aplets is the FUNCTION aplet. Move the cursor
down to this one (using the arrow keys) and press "ENTER". The screen
you are now in is the FUNCTION SYMBOLIC VIEW. If you have defined any
functions already then they should appear here next to the F1(X)=,
F2(X)=, etc. Go to one of these (any one will do, but F1(X)= should be
where your cursor starts) and start typing in your function, say 3X+2.
Just press "3", then "X", "+", and "2". You can enter the "X" by using
the third function button on the top row of the calculator or by
pressing "A...Z" and then "."  Now you should have 3X+2 at the bottom
of the screen. If you press "ENTER" then it will be copied to the
function number you were on and a tick mark will appear next to that
function.

If any other functions have tick marks next to them then you can remove
these by moving to the function and pressing the second function button
on the top row. You can graph more than one function at a time if you
want by "ticking" more than one function. But we'll start off with just
one graph - so untick all the other functions.

If you want to see that graph now, you need to press the "PLOT" button.
The graph should be on the screen now! Sometimes it takes a few seconds
for the HP-38G to plot the graph. To get back to the function screen
where you entered the function press "SYMB". Pressing "NUM" will show
you values of the function for different values of x.

One last hint. When you are in the plot view (after pressing "PLOT")
you can press the sixth (rightmost) function button on the top row to
bring up a menu. This lets you zoom in on the function and do other
neat tricks.

If the graphs still don't work for you then "reset" the function aplet
by going back to the aplet library (press "LIB")  and press "DEL" when
you are on the function aplet. The HP-38G will ask you to confirm that
you want to reset the aplet - this deletes the functions you have
defined and restores all of the options to their defaults. Say yes by
pressing the sixth (rightmost) function button on the top row and try
the steps I gave above again.

solve maths and statistics problems.

Keep experimenting with your calculator - but try to avoid relying on
it too much. You never know when your batteries will run out on your

- Doctor AndrewG, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
High School Calculators, Computers
High School Equations, Graphs, Translations

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