HP 33s - Manual (Page 248)

15–26 Mathematics Programs
Program Lines:
(In RPN mode)
Description

  @
 Complex roots?

 !  Calculate four roots of remaining fourth–order
polynomial.

   If not complex roots, determine largest real root (y
0
)

 º6¸@

 º65¸


 

 º6¸@

 º65¸


!  Stores largest real root of cubic.
Checksum and length: C8B3 180

   Starts fourth–order solution routine.

 

 ! ª  J = a
3
/2.

 ! ª  K = y
0
/2.

 


º


+º Creates 10
–9
as a lower bound for M
2
.

  K

º   K
2
.


.  M
2
= K
2
–a
0
.

 º6¸@

 º If M 2 < 10 –9 , use 0 for M 2 .

 º M =
0
2 a K −
.

 !  Stores M.

   J .

 º  JK .


  a
1
.

 

 ª a
1
/2.


. JK – a
1
/2.

 º/
@

  Use 1 if JK – a
1
/2 = 0