HP 40gs - Manual (Page 251)

Computer Algebra System (CAS) 14-69
Example
Typing:
SIGMA(X · X!, X)
gives:
X!
because (X + 1)! – X! = X · X!.
SIGMAVX Returns the discrete antiderivative of the input function,
that is a function, G, that satisfies the relation: G(x + 1) –
G(x) = f(x). SIGMAVX has as its argument a function f of
the current variable VX.
Example
Typing:
SIGMAVX(X 2 )
gives:
because:
STURMAB Returns the number of zeros of P in [a, b[ where P is a
polynomial and a and b are numbers.
Example 1
Typing:
STURMAB(X 2 · (X 3 + 2), –2, 0)
gives:
1
Example 2
Typing:
STURMAB(X 2 · (X 3 + 2), –2, 1)
gives:
3
2x
3
3x
2
– x +
6
--------------------------------
2 x 1 + ( ) 3
3 x 1 + ( ) 2
– x 1 2x
3
– 3x
2
x – + + + 6x
2
=
hp40g+.book Page 69 Friday, December 9, 2005 1:03 AM