hp40g+.book Page 23 Friday, December 9, 2005 1:03 AM

 

Typing:

 

 

 

 

 

 

 

 

lim⎛N----------------------------------------------------------------⋅TAN(X) – TAN(N ⋅ X )

, 0⎞

 

 

 

⎝

 

SIN(N ⋅ X) – N ⋅ SIN(X)

⎠

 

gives:

 

 

 

 

 

 

 

 

 

2

 

 

 

 

 

 

 

 

 

 

NOTE: To find the limit as x approaches a+(resp a–), the

 

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 – 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.

 

 

 

PREVAL

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).

Computer Algebra System (CAS)

14-23