wrobel's latest activity
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wrobel posted the thread On the Moore–Penrose inverse from a banal linear algebra viewpoint in General Discussion.Usually, the theory of the Moore-Penrose inverse looks like some profound material, but it is actually a combination of several... -
wrobel replied to the thread Is this the correct general solution of the given PDE?.this is an ODE not PDE
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wrobel replied to the thread Is this the correct general solution of the given PDE?.yes and you can reduce it to the standard form by the substitution ##u=e^{-3x+y}w(x,y)##
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wrobel replied to the thread Vector calculus: line element dr in cylindrical coordinates.By the way there is a nice pitfall here. Let ##(x^1,x^2,x^3)## be local coordinates in the domain ##D\subset \mathbb{R}^3## and the...
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wrobel replied to the thread Vector calculus: line element dr in cylindrical coordinates.Perhaps it would be more honest to discuss such things in the proper terms right away: manifold, local coordinates, Riemann metric. It...
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wrobel replied to the thread A mechanical problem with complicated geometry.In particular one can find a distance that the center of the coin passes as the coin makes one complete revolution: $$\Delta...