consider the parametric equations. x=4cost y=5sint -pi/2 theta pi/2
eliminate the parametric to find Cartesian equation of the curve i got x^2/16 + y^2 /25 = 1 but how would i graph it with the arrows ?
start at \(-\frac{\pi}{2}\) or rather that point
oh when you graph it like the direction of the curve
which i think is \((0,-5)\)
|dw:1481078379075:dw|
then go counter clockwise
not sure you go all the way around though
hmm how you know its counterclockwise ?|dw:1481078435813:dw|
cause that is the positive direction, and you are going from \(-\frac{\pi}{2}\) to \(\frac{\pi}{2}\) HOWEVER
i think you only get half the ellipse
ohh
actually now that i look at it that was a lousy answer i gave you know it goes that way because as \(t\) increases from \(-\frac{\pi}{2}\) to \(\frac{\pi}{2}\) , \(y=4\sin(t)\) increases from \(-4\) to \(4\)
ok from -5 to 5 really but you get the idea
and \(x=4\cos(t)\) goes from 0 to 1 and back to 0
but you don't go all the way around the ellipse, since you only have half the period for sine and cosine
ohh k
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