HP 33s - Manual (Page 247)

Mathematics Programs 15–25
Program Lines:
(In RPN mode)
Description
Checksum and length: C7A6 51

   Starts fourth–order solution routine.

 

 º  4a
2
.

   a
3
.

 º   a
32
.

. 4a
2
– a
32
.

º  a
o
(4a
2
– a
32
).

  a
1
.

º   a
12
.


. b
0
=a
0
(4a
0
– a
32
) – a
12
.

 !  Stores b
0
.

   a
2
.

 -+. b
2
= –a
2
.

 !  Stores b
2
.

   a
3
.

 º  a
3
a
1
.




 º  4a
0
.

 . b
1
= a
3
a
1
– 4a
0
.


!  Stores b
1
.

  To enter lines D0021 and D0022;

  press 4 |  3.

 
º


 ª




 - Creates 7.004 as a pointer to the cubic coefficients.


%  Solves for real root and puts a
0
and a
1
for
second–order polynomial on stack.

 ¶ Discards polynomial function value.

 %  Solves for remaining roots of cubic and stores roots.


 % Gets real root of cubic.

 !  Stores real root.