HP 40gs User Manual page 259

hp40g+.book Page 7 Friday, December 9, 2005 1:03 AM
More Examples
Equation Writer
•
Press again and again to progressively select
more of the top-most branch, and then lower
branches (5x, 5x + 3, and then the entire numerator
and finally the entire expression).
Example1
If you enter:
2 + X × 3– X
and press the
entire expression is selected.
Pressing evaluates
what is selected (that is, the
entire expression) and
returns:
2X + 2
If you enter the same expression as earlier but press
after the first X, as in:
2 + X
the 2 + X is selected and the
next operation,
multiplication, is applied to
to it. The expression
becomes:
(2 + X) × 3 – X
Pressing selects the
entire expression, and
pressing evaluates it,
resulting in:
2X + 6
Now enter the same expression, but press
3, as in:
2 + X
Note that selects the
expression so far entered (2
+ X) thus making the next
operation apply to the entire
selection, not just the last
entered term. The key
selects just the last entry (3) and makes the next operation
× 3 – X
after the
× 3 – X
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