HP 39g+ - Manual (Page 151)

Using mathematical functions 11-7
TAYLOR Calculates the nth order Taylor polynomial of expression
at the point where the given variable = 0.
TAYLOR (expression, variable, n)
Example
TAYLOR(1 + sin(s1) 2
,s1,5) with Radians
angle measure and Fraction number format (set in
MODES) returns 1+s1^2-1/3*s1^4.
Complex number functions
These functions are for complex numbers only. You can
also use complex numbers with all trigonometric and
hyperbolic functions, and with some real-number and
keyboard functions. Enter complex numbers in the form
(x,y), where x is the real part and y is the imaginary part.
ARG Argument. Finds the angle defined by a complex number.
Inputs and outputs use the current angle format set in
Modes.
ARG ((x, y))
Example
ARG((3,3)) returns 45 (Degrees mode)
CONJ Complex conjugate. Conjugation is the negation (sign
reversal) of the imaginary part of a complex number.
CONJ ((x, y))
Example
CONJ((3,4)) returns (3,-4)
IM Imaginary part, y, of a complex number, (x, y).
IM ((x, y))
Example
IM((3,4)) returns 4
RE Real part x, of a complex number, (x, y).
RE ((x, y))
Example
RE((3,4)) returns 3