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point B, and its y coordinate (that is, its ordinate) to always
equal the slope of the derivative at that point.
16. To define a point in
terms of the attributes of
other geometric objects,
you need to go to
Symbolic view:
Y
Note that each object
you have so far created
is listed in Symbolic view. Note too that the name for an
object in Symbolic view is the name it was given in Plot
view but prefixed with a "G". Thus the graph—labeled A
in Plot view—is labeled GA in Symbolic view.
17. Highlight GC and tap
When creating objects that are dependent on other
objects, the order in which they appear in Symbolic view
is important. Objects are drawn in Plot view in the order
in which they appear in Symbolic view. Since we are
about to create a new point that is dependent on the
attributes of GB and GC, it is important that we place its
definition after that of both GB and GC. That is why we
made sure we were at the bottom the list of definitions
before tapping
higher up in Symbolic view, the point we are about to
create wouldn't be drawn in Plot view.
18. Tap
and choose Point > point
You now need to specify the x and y coordinates of the
new point. The former is to be constrained to abscissa of
point B (referred to as GB in Symbolic view) and the later
is to constrained to the slope of C (referred to as GC in
Symbolic view).
19. You should have point() on the entry line. Between
the parentheses, add:
abscissa(GB),slope(GC)
You can enter the commands by hand, or choose them from
the
menu (one of the five Toolbox menus).
Catlg
.
. If our new definition appeared
Geometry