HP 40gs - Polynomial Menu

Computer Algebra System (CAS) 14-55
SUBTMOD Performs a subtraction in Z/pZ or Z/pZ[X].
Example 1
Typing:
SUBTMOD(29, 8)
gives:
–5
Example 2
Typing:
SUBTMOD(11X + 5, 8X + 6)
gives:
Polynomial menu
EGCD Returns Bézout’s Identity, the Extended Greatest Common
Divisor (EGCD).
EGCD(A(X), B(X)) returns U(X) AND V(X) = D(X), with D,
U, V such that D(X) = U(X)·A(X) + V(X)·B(X).
Example 1
Typing:
EGCD(X
2
+ 2 · X + 1, X
2
– 1)
gives:
AND
Example 2
Typing:
EGCD(X
2
+ 2 · X + 1, X
3
+ 1)
gives:
AND
3x 1–
1–1–2x 2+=
x 2–()–13x 3+=
hp40g+.book Page 55 Friday, December 9, 2005 12:27 AM