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| visits | member for | 1 year, 2 months |
| seen | 18 hours ago | |
| stats | profile views | 415 |
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17h |
comment |
How to calculate this multi-integral? Apply Fubini's Theorem. |
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2d |
accepted | A typo in Spivak's solution? |
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2d |
accepted | An almost upper bound. Is this a counter example? (SPIVAK) |
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May 18 |
accepted | $\sup (A+B) = \sup A + \sup B$ |
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May 14 |
comment |
Sufficient condition to a function be a diffeomorphism What about its inverse? |
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May 13 |
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$\sup (A+B) = \sup A + \sup B$ Sorry for my belated answer. I had to go to the hospital last night. If a number is smaller than every real number, then doesn't that mean the number does not exist? I seriously need a concrete numerical example |
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May 11 |
answered | proving that a certain function is not differentiable at $(0,0)$ |
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May 11 |
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$\sup (A+B) = \sup A + \sup B$ From your implication, you have for every z greater than x that is as big as y, then we have $x \geq y$ |
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May 11 |
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$\sup (A+B) = \sup A + \sup B$ Regarding my example we have the following: 5 > 4 and $5 \geq 4$ implies 5 > 5 whichh is a false statement |
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May 10 |
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When is $\det(A+B)=\det(A)+\det(B)$ for positive definite $A$ and positive semidefinite $B$? The 0 matrix and identity works. Maybe a few more |
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May 10 |
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$\sup (A+B) = \sup A + \sup B$ How do I even know when to use this epsilon trick? It was actually given as a hint, I am not so sure when to even use it |
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May 10 |
reviewed | Approve suggested edit on Proving that if $\inf S\notin S$, then it is an accumulation point of $S$ |
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May 10 |
answered | Prove that $f$ is continuous at a if and only if $\lim _{h\to0} f (a + h) = f(a)$ |
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May 10 |
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$\sup (A+B) = \sup A + \sup B$ "If every real number bigger than x is at least as big as y..."So if $z = 5$ (say) and $x = 4$, and $y = 5$. Something is wrong |
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May 9 |
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$\sup (A+B) = \sup A + \sup B$ But then what would be the point of defining the equality in this question? |
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May 9 |
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$\sup (A+B) = \sup A + \sup B$ Isn't it meangingless to talk about the supremum if the set isn't bounded in the first place? |
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May 9 |
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$\sup (A+B) = \sup A + \sup B$ I accept the truth of your explanation, but I have no intuition or feeling behind it. The whole $\epsilon$ thing is the one thing that's bugging me |
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May 8 |
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An almost upper bound. Is this a counter example? (SPIVAK) Coudl you look at my updated question? |
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May 8 |
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Differentiability of function $f(x,y) = |x|^a + |x-y|$. The way I see it, it appears you have no choice but to do it by brute force. That is we have to compute the derivative from the formal definition. I only worked out one partial derivative and it was quite involved already. Many inequalities |
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May 8 |
revised |
An almost upper bound. Is this a counter example? (SPIVAK) edited tags |
