HP HP-25 - Trigonometric and Logarithmic Functions

Trigonometric
Functions
Your
HP-25
provides
you
with
six
trigonometric
functions.
It
also
calculates
angles
in
decimal
degrees,
radians,
or
grads;
and
it
converts
between
decimal
degrees
and
degrees,
minutes,
seconds.
Trigonometric Modes
When
the
HP-25
is
first
turned
ON,
it
“‘wakes
up’’
with
angles
specified in decimal degrees. To set radians or grads mode,
press the ] shift key followed by either [rap](radians) or
(grads).
To
switch
back
to
the
decimal
degrees
mode
again,
press the [Elshift key followed by the [bEc](degrees) key.
Note: 360 degrees = 27 radians = 400 grads
Functions
The six trigonometric functions provided by the calculator are:
[sin] (sine)
B8 (arc sine)
B (cosine)
B (arc cosine)
B (tangent)
3 [tan'] (arc tangent)
Each trigonometric function assumes angles in decimal degrees,
radians, or grads. Trigonometric functions are one-number
functions, so to use them you key in the number, then press the
function keys.
Example 1: Find the cosine of 35°.
Press Display
35 B Calculator “‘wakes up’” in
decimal degrees mode.
The answer.
Example 2: Find the arc sine in grads of .964.
Press Display
964
9] 0.96 Grads mode is set.
e 82.87 Grads.