Texas Instruments TI-83 PLUS - Manual (Page 92)

TI-83 Plus Math, Angle, and Test Operations 89
real(
real( (real part) returns the real part of a complex number or list of
complex numbers.
real( a + bi ) returns a .
real( r e^( qi )) returns r ä cos ( q ).
imag(
imag( (imaginary part) returns the imaginary (nonreal) part of a complex
number or list of complex numbers.
imag( a + bi ) returns b .
imag( r e^( qi )) returns r ä sin( q) .