### Author Topic: sketch a graph  (Read 1237 times)

#### Jiacheng Ge

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##### sketch a graph
« on: November 01, 2018, 11:40:54 PM »
What's the strategy to sketch a graph of the solution in the x1- x2 plane for t>0?

#### Monika Dydynski

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##### Re: sketch a graph
« Reply #1 on: November 02, 2018, 10:17:47 AM »
For assigned exercises 8-12 in 7.1, the solutions are equations in parametric form, $x_1(t)$ and $x_2(t)$.

Each value of $t$ gives a point $(x_1(t), x_2(t))$ on the curve in the $(x_1,x_2)$-plane.

One way to sketch the graph of the solution in the $(x_1,x_2)$-plane for $t \ge0$ is to evaluate $x_1(t)$ and $x_2(t)$ at different values of $t \ge 0$, where $x_1$ is the horizontal axis and $x_2$ is the vertical axis.

Not sure if there is a more efficient way of doing this.