Recent content by rbnvrw

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    Find the critical points of (x^2+y^2-4)(x+y) and their nature

    Yes! I got it! Thank you for your help, I appreciate it! :D
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    Find the critical points of (x^2+y^2-4)(x+y) and their nature

    Oops... I see it now. I used f(x,y) instead of the partial derivatives. I will try again!
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    Find the critical points of (x^2+y^2-4)(x+y) and their nature

    I got this: y = \pm x (x^2+x^2-4)(x+x)=0 x(x^2-2)=0 x = 0 \vee x=\pm \sqrt{2} According to the solutions manual, which only states the values, not the method, the solutions are: x = \pm \sqrt{2} \vee x = \pm \sqrt{\frac{2}{3}}
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    I have a couple questions on gravity

    So, if you want to calculate the gravitational force a massive object of mass M exercises on some other mass m, it would be done like this: F_G = -G\frac{mM}{r^2}. Where F_G is the gravitational force, G the gravitational constant and r the distance between the two objects. (either as size or...
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    Find the critical points of (x^2+y^2-4)(x+y) and their nature

    Thanks for your advice. However, this doesn't give me the four points of intersection. If I take the solutions y=\pm x, I get the solutions (0,0) \wedge (\pm \sqrt{2},\pm \sqrt{2}). However, the points (\pm \sqrt{\frac{2}{3}},\pm \sqrt{\frac{2}{3}}) are also solutions of the equation. And...
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    Electrostatic Potential Concept

    This is because you are dealing with electrostatics. If the charge is moving rapidly, you are dealing with electrodynamics and magnetic fields. I don't really know what exactly is slow enough to be described by electrostatic theorems, though.
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    Find the critical points of (x^2+y^2-4)(x+y) and their nature

    Hi, I am studying for my Analysis final and came across this problem I just can't get my head around: Homework Statement Find the critical points of f(x,y) = (x^2+y^2-4)(x+y) and their nature. Homework Equations \vec{\nabla} f(x,y) = \vec{0} The Attempt at a Solution \frac{\partial...
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    Electric field of a loop with one positive halve and one negative halve

    Thanks for your answer! So, I tried to draw the contributions. Am I correct that inside the circle the dE due to the negative charge points toward the negative charge and dE due to the positive charge also points in that direction, thus doubling the field? Or is this too naive? For a point...
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    Physics Vector point Problem

    Well, the plane is defined as \vec{r} \cdot \vec{n} = 0. This states that r is perpendicular to n. So every point r for which this equation holds, lies in the plane. See also this page on planes: http://mathworld.wolfram.com/Plane.html. Hope this helps!
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    Electric field of a loop with one positive halve and one negative halve

    Homework Statement Given a circular wire with radius R. Choose the origin in the center of the circle, the z-axis perpendicular to the circle. One halve of the circle contains a positive line charge \lambda, the other halve a negative line charge of the same magnitude. (a) Sketch the electric...
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