Casio fx-CG10 Advanced Operation Manual page 80

Sample Solution—Thrill of the Ride (continued)
The calculator allows you to enter a function which describes the slope at each
point of the curve. This function is called the derivative. Similar to delta y
over delta x, this function appears as
Highlight Y Y 2 and
Press
Press
Make sure both Y Y 1 and Y Y 2 are selected (as shown) and press
draw them. In our graph, the quartic function is drawn in blue and the
derivative function, which shows the slope at each point, is shown in red.
Note: the red graph is positive in the sections where the track (shown in
blue) is rising, negative when the track is falling, and on the x-axis where
the change occurs.
We want to find where the track is falling the fastest:
Press
Y1 will be flashing but we want Y Y 2; press
press
Fostering Advanced Algebraic Thinking with Casio Technology
, (CALC), then
(Y) and to indicate Y Y 1. Press
(G-Solv) and
.
dy
.
dx
(d/dx).
.
(MIN).
so that Y Y 2 is flashing and
(DRAW) to