Texas Instruments Voyage 200, Руководство пользователя

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Symbolic Manipulation 252
Note:
Enter
ln(x
†
y)
instead of
ln(xy)
; otherwise, xy is interpreted as a single variable
named xy.
Note:
For
‚
or

, press
8 Ã
or
8 Â
. You can also use
2 I
8
or
2 G
2
to
select them from a menu.
Using Substitutions vs. Defining a Variable
Using Substitutions vs. Defining a Variable Using Substitutions vs. Defining a Variable
Using Substitutions vs. Defining a Variable
However, substitution is preferable for most cases because the variable is defined only
for the current calculation and does not accidentally affect later calculations.
Because sin
L
1
(sin(
q
)) =
q
is not always valid, the
expression is not simplified.
With a constraint, the expression can be simplified.
In many cases, you can achieve the same
effect as a substitution by defining the
variable.
Substituting x=1 does not affect the next
calculation.