HELP!
i got C @asnaseer
@AMYCARTER
@SithsAndGiggles PLEASE HELP
i just need someone to check my answer please
Have you tried solving any of these ODEs? They are all separable, so not too difficult.
Before you try that, though, I'm sure there's an easier (but somewhat tedious) way to approach this. Pick some points from the graph, like the \((1,1)\) and \((-1,-1)\), for example, and plug them into the DE. This way you can eliminate which ODEs are NOT satisfied. For example, take \((-1,-1)\). You get \[\begin{matrix}\frac{dy}{dx}_A=\frac{-1}{(-1)^2}=-1&&\frac{dy}{dx}_B=\frac{-1}{-1}=1\\\\ \frac{dy}{dx}_C=\frac{(-1)^2}{-1}=-1&&\frac{dy}{dx}_D=\frac{(-1)^2}{(-1)^2}=1 \end{matrix}\] According to the slope field, at \((-1,-1)\), the slope appears to be negative, so you can eliminate B and D.
thats such a more simple way to do it...i took up like a whole page
but i think we both got the same answer whih was C
Yes, that's right. If you try the point \((-1,1)\) or \((1,-1)\), you'll eliminate A.
thanks so much(:
it would be parabolas right?
@SithsAndGiggles
Not parabolas, no. You can tell by solving - there are a few ways, but treating this as a separable is easiest. \[\begin{align*}x\,dx+y\,dy&=0\\ y\,dy&=-x\,dx\\ \int y\,dy&=-\int x\,dx\\ \frac{1}{2}y^2&=-\frac{1}{2}x^2+C\\ y^2+x^2&=C^* \end{align*}\] Which conic is this?
hyperbola @SithsAndGiggles
No, not hyperbola
oh wait circle
right? @SithsAndGiggles
Yes, a circle. Remember, \(x^2+y^2=r^2\) is a circle with radius \(r\).
thanks for the help(:
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