sketch

logistic_guy

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Apr 17, 2024
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Sketch.

r(t)=(t+1)i+(t22)j\displaystyle \bold{r}(t) = (t + 1)\bold{i} + (t^2 - 2)\bold{\bold{j}}
 
We can write this curve in terms of x\displaystyle x and y\displaystyle y if we are smart enough. Then, it is a piece of cake to recognize its graph!

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x=t+1\displaystyle x = t + 1

This means:

t=x1\displaystyle t = x - 1

This gives:

y=t22=(x1)22\displaystyle y = t^2 - 2 = (x - 1)^2 - 2

This is just the graph of a parabola that is shifted one unit to the right and two units downward and concaves upward with its vertex at (1,2)\displaystyle (1,-2)

curve.png

Since this is a parametrized curve, we expect it contains a path. It should be counterclockwise in this case. Why? Think about it!

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