hp40g+.book Page 69 Friday, December 9, 2005 1:03 AM

 

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(X2)

 

gives:

 

2x3 – 3x2 + x

 

-------------------------------

 

6

 

because:

 

2(x + 1)3 – 3(x + 1)2 + x + 1 – 2x3 + 3x2 – x = 6x2

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(X2 · (X3 + 2), –2, 0)

 

gives:

 

1

 

Example 2

 

Typing:

 

STURMAB(X2 · (X3 + 2), –2, 1)

 

gives:

 

3

Computer Algebra System (CAS)

14-69