HP 40gs User Manual page 195

PARTFRAC
QUOTE
Computer Algebra System (CAS)
In real mode, the result is:
2
( 2 x ⋅
x + + 1
In complex mode (using CFG), the result is:
1
⋅ ( ( )
----- -
2x + 1 + i
16
⋅ ( ( ) ⋅
2x 1 i – – 2
Partial fraction expansion
PARTFRAC has a rational fraction as an argument.
PARTFRAC returns the partial fraction decomposition of
this rational fraction.
Example
To perform a partial fraction decomposition of a rational
function, such as:
------------------------------------------------------------------------ -
4
x –
you use the PARTFRAC command.
In real and direct mode, this produces:
x + +
In complex mode, this produces:
x + + 2
Quoted expression
QUOTE(expression) is used to prevent an expression
from being evaluated or simplified.
Example 1
Typing:
⎛
im QUOTE 2X 1
⎝
gives:
+∞
2
) ⋅ ( 2 x ⋅
x – + 1
⋅ ) ⋅ ( ( )
2 2x 1 – + i
)
5 3
⋅
x – 2 x + 1
3 2
⋅ ⋅ (
2 x + 2 x – 2 x
x 3 –
--------------------- - ------------------ -
2 +
2 x ⋅ 2
2
⋅
2 x + 2
1 3i – 1 –
------------- - ----- -
4 2
------------- - ---------- -
+ +
x + i x 1 –
1
( ( ) ⋅ -- - 1 )
– EXP(
X
)
⋅ ) ⋅ ( ( )
2 2x + 1 i –
⋅ )
+ 1
1 –
–
1 + 3i
------------- -
4
------------- -
x i –
⎞
,
– X = +∞
⎠
14-13
⋅ )
2