HP 40gs User Manual
Page 230
14-48
Computer Algebra System (CAS)
In step-by-step mode, there are a number of intermediate
results:
18 mod 15 = 3
15 mod 3 = 0
Result: 3
Pressing
or
then causes 3 to be written to the
Equation Writer.
Note that the last non-zero remainder in the sequence of
remainders shown in the intermediate steps is the GCD.
IDIV2
Returns the quotient and the remainder of the Euclidean
division between two integers.
Example
Typing:
IDIV2(148, 5)
gives:
29 AND 3
In step-by-step mode, the
calculator shows the
division process in
longhand.
IEGCD
Returns the value of Bézout’s Identity for two integers. For
example, IEGCD(A,B) returns U AND V = D, with U, V, D
such that AU+BV=D and D=GCD(A,B).
Example
Typing:
IEGCD(48, 30)
gives
2 AND –3 = 6
In other words: 2·48 + (–3)·30 = 6 and GCD(48,30) = 6.
In step-by-step mode, we get:
[z,u,v]:z=u*48+v*30
hp40g+.book Page 48 Friday, December 9, 2005 1:03 AM