HP HP-28S User Manual

Real Numbers
Real numbers represent numbers greater than _10
500
and less than
10
500
.
They are stored internally as a mantissa between 1 and
9.99999999999, a sign (positive or negative) for the mantissa, an expo-
nent between 0 and 499, and a sign for the exponent.
In Hours-Minutes-Seconds Format.
You can use the commands
HMS + and HMS - to add and subtract numbers expressed as hours,
minutes, and seconds (or degrees, minutes, and seconds). For any
computation other than addition or subtraction, first use HMS- to
convert the numbers from HMS format to decimal degree format. (See
"TRIG" in
the Reference Manual for details.)
Complex Numbers
Complex-number objects are ordered pairs of real numbers that repre-
sent the real part and the imaginary part of a complex number or the
coordinates of a point in a plane.
Rectangular and Polar Coordinates. In
chapters 7 and 8 you used
complex numbers for plotting and digitizing; each complex number
represented rectangular coordinates-that is, distances along per-
pendicular axes.
Chapter 6 described polar coordinates-a radial distance and an an-
gle-and used the commands R-P and P-R to convert between polar
and rectangular coordinates. You can use polar coordinates to key in
coordinates and to display results, but you must use rectangular co-
ordinates for calculations. The user function PSUM, described on
page 86, adds points in polar coordinates by converting them, adding
them, and reconverting them.
In AlgebraiC Objects. When you key in a complex number in an
algebraic object, you may need two pairs of parentheses, as in the
expression I S I t·l 0:: 0:: 0, 1 :; :; I. The outer pair of parentheses are re-
quired by the function S I ~l 0:: :;, while the inner pair are delimiters
for complex
numbers.
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HP HP-28S Specifications

General

Brand	HP
Model	HP-28S
Category	Calculator
Language	English