HP 40gs User Manual page 234

hp40g+.book Page 52 Friday, December 9, 2005 1:03 AM
DIVMOD
EXPANDMOD
14-52
Division in Z/pZ or Z/pZ[X].
Example 1
In Z/pZ, the arguments are two integers: A and B. When
B has an inverse in Z/pZ, the result is A/B simplified as
Z/pZ.
Typing:
DIVMOD(5, 3)
gives:
6
Example 2
In Z/pZ[X], the arguments are two polynomials: A[X] and
B[X]. The result is a rational fraction A[X]/B[X] simplified
as Z/pZ[X].
Typing:
2
DIVMOD(2X + 5, 5X
gives:
4x + 5
-------------- -
–
3x + 3
Expand and simplify expressions in Z/pZ or Z/pZ[X].
Example 1
In Z/pZ, the argument is an integer expression.
Typing:
EXPANDMOD(2 · 3 + 5 · 4)
gives:
0
Example 2
In Z/pZ[X], the argument is a polynomial.
Typing:
2
EXPANDMOD((2X + 12)·(5X – 4))
gives:
3 2
( ⋅ ⋅ 5 x ⋅ 4
– 3 x – 5 x +
2
+ 2X –3)
)
–
Computer Algebra System (CAS)