Value of x of which a slope is undefined for a parametric graph.
By Michael Henderson •
For what values of $x$ is the slope undefined for the graph
$$x=8-t^3$$
$$y=t^2-6t$$
The slope should be undefined when $\frac {dx}{dt}=0$.
$$\frac {dx}{dt}=-3 t^2$$
$$-3t^2=0$$
$$t=0$$
When $t=0$, $x=8$ so the $x$ value should be $8$, but the question was marked incorrect. What is incorrect in this?
$\endgroup$ 61 Answer
$\begingroup$Answer was x=8, question incorrectly marked.
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