HP 15c Collector's Edition

136 Section 11: Calculating With Complex Numbers
Keystrokes
Display
2 ´ }
0.0000
2i. Display shows real part.
8 ” v
-8.0000
6 ´ V
-8.0000
−8 + 6i.
3 y
352.0000
(−8 + 6i)
3
.
*
-1.872.0000
2i (−8 + 6i)
3
.
4 v
4.0000
5 ¤
2.2361
2 ” *
-4.4721
−2

5.
´ V
4.0000
4

−

2

5i.
÷
-295.4551
2i

−8

+

6i

3
4

−

2

5
i
.
2 v 5 ¤
2.2361
4 ” *
-8.9443
´ V
2.0000
2 −

4

5i.
÷
9.3982
Real part of result.
´ %
-35.1344
Answer: 9.3982 − 35.1344i.
9.3982
2.
Write a program to evaluate the function ω =
2
z
+

1
5z +

3
for different
values of z. (ω
represents a linear fractional transformation, a class
of conformal mappings.) Evaluate ω for z = 1 + 2i.
(Answer: 0.3902 + 0.0122
i
. One possible keystroke sequence is:
´
b A v v 2 * 1 + ® 5 * 3 + ÷
¦ ´ } | n .)
3.
Try your hand at a complex polynomial and rework the example on
page 80. You can use the same program to evaluate P(z) = 5z
4
+
2z
3
, where z is some complex number.
Load the stack with z = 7 + 0i and see if you
get the same answer
as before.
(Answer: 12,691.0000 + 0.0000i.)
Now run the program for z = 1 + i.
(Answer −24.0000 + 4.0000i.)