Complex Numbers - HP 15C Quick Reference Manual

Memory
f I -or-
Re↔Im
Real number
Imaginary
number
f I
f (i)
Re↔Im
CHS
CLx or ←
STO & RCL
x↔y
R↓ R↑
Sqrt x² Ln Log
1/x e x
hyp sin cos tan
hyp -1 sin cos tan
ABS
+ - x ÷ y x
sin cos tan
sin -1 cos -1 tan -1
→ P
→ R
Conditional tests

Complex Numbers

In complex mode a complex stack including Last-X register exists.
The needed five registers are allocated from the uncommitted
memory space, see MEM.
Automatically turns on the complex mode. Indicated by "C" in the
display. To turn off complex mode clear flag 8 (CF8).
NOTE: If stack lift is enabled and a number is keyed in, a stack lift
occurs and the imaginary part is set to 0!
If stack lift is enabled: Enter real part
If stack lift is enabled: Enter real part, press Re↔Im
Complex number input: <real part> ENTER <imaginary part> f I
Display imaginary part of number while (i) is held down
Exchange real and imaginary part
Changes sign of real part only! Use Re↔Im to negate the imaginary
part as well
Clears only the real part. However, this disables stack lift for both the
real and imaginary stack so the entry of a complex number after "←"
will do the expected thing
STO & RCL only act on the real part of the number!
Store: STO 1, Re↔Im, STO 2, Re↔Im
Recall: RCL 2, RCL 1, f I -or-
RCL 2, Re↔Im, ←, RCL 1 (this does not disturb the stack)
Replace both real and imaginary part of X and Y register
Shift both the real and imaginary part
All these unary functions work in complex mode as well.
NOTE: To calculate sqrt(-1) the complex mode must be already
enabled or otherwise an error occurs!
Calculates magnitude of complex number
All these binary functions work in complex mode as well
Trigonometric functions are only executed in radians (2π)
Convert from rectangular coordinates (real=X, imaginary=Y) to polar
coordinates (real=R, imaginary=θ).
This operation is affected by the current trigonometric setting
(DEG,RAD, GRD)
Convert from polar coordinates (real=R, imaginary=θ) to rectangular
coordinates (real=X, imaginary=Y).
This operation is affected by the current trigonometric setting
(DEG,RAD, GRD)
These tests work for complex numbers and operate on both the real
and imaginary part: x=y, TEST 0 (X≠0), TEST 5 (X=Y), TEST 6 (X≠Y)
All other tests ignore the imaginary part of the complex number
HP-15C
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