HP 40gs User Manual page 205

hp40g+.book Page 23 Friday, December 9, 2005 1:03 AM
PREVAL
Computer Algebra System (CAS)
Typing:
N TAN X ( ) TAN N X ) ⋅
–
⎛
---------------------------------------------------------------- - 0 ,
lim
⎝
( ⋅ ) N SIN X ( )
SIN N X –
gives:
2
NOTE: To find the limit as x approaches a
second argument is written:
X=A+0(resp X=A-0)
For the following expression, find the limit as x
approaches +∞:
x + x + x – x
Typing:
⎛
lim X + X + X –
⎝
produces (after a short wait):
1
-- -
2
NOTE: the symbol ∞ is obtained by typing SHIFT 0.
To obtain –∞:
(–)∞
To obtain +∞:
(–)(–)∞
You can also find the symbol ∞ in the MATH key's
Constant menu.
Evaluate a primitive
PREVAL has three parameters: an expression F(VX)
dependent on the variable contained in VX, and two
expressions A and B.
For example, if VX contains X, and if F is a function,
PREVAL (F(X),A,B) returns F(B)-F(A).
( ⋅
⎞
⎠
⋅
+ –
(resp a
⎞
∞
X , +
⎠
), the
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