Texas Instruments TI-84 - Manual (Page 76)

Chapter 2: Math, Angle, and Test Operations 73
On the TI-84 Plus, complex numbers can be stored to variables. Also, complex numbers
are valid list elements.
In Real mode, complex-number results return an error, unless you entered a complex
number as input. For example, in Real mode
ln( L 1) returns an error; in a+bi mode ln( L 1)
returns an answer.
Entering Complex Numbers Entering Complex Numbers Entering Complex Numbers Entering Complex Numbers
Complex numbers are stored in rectangular form, but you can enter a complex number
in rectangular form or polar form, regardless of the mode setting. The components of
complex numbers can be real numbers or expressions that evaluate to real numbers;
expressions are evaluated when the command is executed.
Note about Radian Versus Degree Mode Note about Radian Versus Degree Mode Note about Radian Versus Degree Mode Note about Radian Versus Degree Mode
Radian mode is recommended for complex number calculations. Internally, the TI-84
Plus converts all entered trigonometric values to radians, but it does not convert values
for exponential, logarithmic, or hyperbolic functions.
Real mode a+bi mode
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