HP 40gs User Manual page 261

hp40g+.book Page 9 Friday, December 9, 2005 1:03 AM
Equation Writer
Select the fifth branch by
pressing . At this point,
the desired expression is in
the Equation Writer, as
shown at the right.
Suppose that you want to select the second and third
1 1
-- - -- -
+
branches, that is: . First press
3 4
the second term.
Now press . This
key combination enables
you to select two contiguous
branches, the one already
selected and the one to the
right of it.
If you want, you can
evaluate the selected part by
pressing . The result
is shown at the right.
Suppose now you want to
perform the partial calculation:
Because the two terms in this partial calculation are not
contiguous (that is, side by side), you must first perform a
permutation so that they are side by side.To do this,
press:
This exchanges the selected
element with its neighbour to
the left. The result is shown at
the right.
Now press:
to select just the branches
you are interested in:
. This selects
1 1
-- - -- -
+
2 5
1
-- -
,
3
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