HP 40gs - Page 234

14-52 Computer Algebra System (CAS)
DIVMOD 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:
DIVMOD(2X
2
+ 5, 5X
2
+ 2X –3)
gives:
EXPANDMOD 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:
EXPANDMOD((2X
2
+ 12)·(5X – 4))
gives:
4x 5+
3x 3+
---------------
–
3 x
3
⋅ 5 x
2
⋅–5x⋅ 4–+()–
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