HP 40gs - 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 12x
3
–3x
2
x–++ + 6x
2
=
hp40g+.book Page 69 Friday, December 9, 2005 12:27 AM