HP 40gs User Manual page 249

hp40g+.book Page 67 Friday, December 9, 2005 1:03 AM
LAP
PA2B2
PSI
Computer Algebra System (CAS)
Typing:
1
⎛ (
--------------------------- -
+
2
⎜
X – 6X + 9
⎜ ------------------------------------------------------------------ -
ILAP
2
⎜
X – 6X
⎝
gives:
3
x
⎛ ⎞ e
( ) ⋅
---- -
– 3a b – x + a
⎝ ⎠
6
See ILAP above.
Decomposes a prime integer p congruent to 1 modulo 4,
as follows:
2 2
p = a + b .
The calculator gives the result as a + b · i.
Example 1
Typing:
PA2B2(17)
gives:
4 + i
2 2
that is, 17 = 4 + 1
Example 2
Typing:
PA2B2(29)
gives:
5 + 2 · i
2 2
that is, 29 = 5 + 2
Returns the value of the nth derivative of the Digamma
function at a.
The Digamma function is the derivative of ln(Γ(x)).
Example
Typing:
PSI(3, 1)
) a ⋅ ⎞
X 6 – + b
⎟
⎟
⎟
+ 9
⎠
3 x
⋅
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