17
K
K
E
E
Y
Y
S
S
&
&
N
N
O
O
T
T
A
A
T
T
I
I
O
O
N
N
C
C
O
O
N
N
V
V
E
E
N
N
T
T
I
I
O
O
N
N
S
S
There are a number of types of keys/buttons that are used on the hp 39g+.
S
S
o
o
m
m
e
e
e
e
s
s
s
s
e
e
n
n
t
t
i
i
a
a
l
l
k
k
e
e
y
y
s
s
The basic keys are those that you see on any
calculator including scientific ones, such as the
numeric operators and the trig keys. Most of these
keys have two or more functions.
Take for example the
COS
key shown left. If
you just press the key, you get the
COS
function.
However above left of the key and below right
you will see two additional meanings assigned
via the
SHIFT
and
ALPHA
keys.
All references to keys, whether they need the
SHIFT
key or not, are written in
this typeface:
KEY
.
The SHIFT key
The
SHIFT
key gives you the second function for each
key. In the case of the
COS
key, the second function is
ACOS
, sometimes referred to as arc-cos or cos
-1
or
inverse cos. Most keys have these second functions that
are obtained via the
SHIFT
key.
When I want you to use one of these keys that needs to
have the
SHIFT
key pressed first I usually won’t say so.
It seems to me that you’re intelligent enough to work out
for yourself when the
SHIFT
key needs to be pressed.
