14-3-2

Graphing a Second Order Differential Equation

(4)Tap .

• This draws the phase plane of x’ = x, y’ = −y.

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[Edit] - [Redraw]

Inputting Initial Conditions and Graphing the Solution Curve of a Second Order Differential Equation

You can use the procedure in this section to overlay, onto the slope field, solution curve of the second order differential equation input on the [DiffEq] tab for given initial conditions.

Example: To input the second order differential equation {x’ = x, y’ = −y}, draw the phase plane, and then graph the solution curve of the initial condition (xi, yi) = (1, 1)

The independent variable minimum value (tmin) = −7.7, maximum value (tmax) = 7.7, and initial value (t0) = 0.

SClassPad Operation

(1)Use the procedure under “Drawing the Phase Plane of a Second Order Differential Equation” on page 14-3-1 to draw the phase plane for {x’ = x, y’ = −y}.

(2)Activate the Differential Equation Editor window and then tap the [IC] tab.

• This displays the initial condition editor.

(3)Input (xi, yi) = (1, 1) into the initial condition editor.

Select the check box next to “xi=” and then tap

@U@U.

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