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HP Prime Graphing Calculator User Manual

Page 143

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Geometry

139

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
one of two Toolbox menus: App > Measure, or

Catlg

.

20.Tap .

The definition of your
new point is added to
Symbolic view. When
you return to Plot view,
you will see a point
named D and it will

have the same x-
coordinate as point B.

21. Press

P

.

If you can’t see point D,

pan until it comes into
view. The y coordinate
of D will be the

derivative of the curve at
point B.
Since its difficult to read
coordinates off the screen, we’ll add a calculation that
will give the exact derivative (to three decimal places)
and which we can display in Plot view.

Add some

calculations

22. Press

M

.

Numeric view is where you enter calculations.

23. Tap .
24.Tap

and choose Measure > slope

25.Between parentheses, add the name of the tangent,

namely GC, and tap

.

Notice that the current slope is calculated and displayed.
The value here is dynamic, that is, if the slope of the