Casio ClassPad II fx-CP400 Examples - Manual (Page 20)

Chapter 5: Differential Equation Graph Application 20
0503
1. On the Differential Equation Editor window, tap [Type] - [2nd (Phase Plane)] or
B.
2. Xw-Yw 3. Tap O to draw the phase plane.
0504
1. Activate the Differential Equation Editor window and then tap the [IC] tab.
• This displays the initial condition editor.
2. Input ( xi , yi ) = (1, 1) on the initial condition editor.
3. Tap
O.
• This graphs the solution curve and overlays it on the phase plane of x ’ = x ,
y ’ = − y .
0505
1. On the Differential Equation Editor window, tap [Type] - [Nth (No Field)] or 9.
2. Input y ’’ = x − y by dividing it into two first order differential equations. If
we let y 1 = y and y 2 = y ’, we see that y 1’ = y ’ = y 2 and y 2’ = y ’’ = x − y 1.
Ycw
X-Ybw
3. Tap the [IC] tab to display the initial condition editor.
4. Input ( xi , y 1 i , y 2 i ) = (0, −1, 0), (0, 0, 0), (0, 1, 0). 5. Tap
O.
LY777Ex_E.indb 20 13/02/25 11:23