There are two ways that functions can be used in the CAS. The first is to use them as the expression is entered.
In this method the order is to choose the function and then to fill in the parameters required. The second is to
apply a function to all or part of an expression that has perhaps resulted from a previous calculation or been
typed in first. If you highlight an expression and then choose a function the expression will appear as the first
parameter in the function. A list of the functions in their various menus is given on page 358.
Example 3:
Using lim
2
x
−
2
x
−
35
i)
Find
lim
.
x
→
7
x
−
7
The sequence of keys for this is…
scroll to
lim
and press
ENTER
- 2
- 35
- 7
7
ENTER
1
ii)
Find
lim
.
x
→
2
−
x
−
2
The sequence of keys for this is…
scroll to
lim
then
ENTER 1
- 2
MATH
scroll to
QUOTE ENTER 2 - 0
SHIFT
ENTER ENTER
Some notes:
1.
The limit approached from above would be
entered as
QUOTE(2 + 0)
.
2.
The use of the
QUOTE
function forces the CAS to treat the “
2 - 0
” as
an algebraic entity rather than immediately evaluating it as simply “2”. Thus the result of
−∞
.
3.
The two functions
LIMIT
and
lim
are the same. On the old model hp 40g the only function was
LIMIT
but
lim
was added on the 40gs. Because it was a late entry it appears one way in some menus and as
the alternative in the others. Functionally there is no difference so why it was added is not clear.
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