TI-83 Plus Math, Angle, and Test Operations 85
Real mode a+bi mode
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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
Radian mode is recommended for complex number calculations.
Internally, the TI-83 Plus converts all entered trigonometric values to
radians, but it does not convert values for exponential, logarithmic, or
hyperbolic functions.
In degree mode, complex identities such as e^(iq) = cos(q) + i sin(q) are
not generally true because the values for cos and sin are converted to
radians, while those for e^() are not. For example, e^(i45) = cos(45)
+ i sin(45) is treated internally as e^(i45) = cos(p/4) + i sin(p/4). Complex
identities are always true in radian mode.