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| bio | website | |
|---|---|---|
| location | Houston, TX | |
| age | 30 | |
| visits | member for | 2 years, 5 months |
| seen | May 8 at 14:13 | |
| stats | profile views | 48 |
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Dec 22 |
comment |
Is a counterexample considered a rigorous proof that a property is not true? An existential statement is proved by an example, not a counterexample. Your whole answer is a bit fuzzy about when you're talking about the universal claim, and when you are talking about the existential inverse of the universal claim. |
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Nov 1 |
comment |
How many iterations can I have in a year Is it a leap year? If you start on day 1, does it end on day 8 or day 9? |
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Sep 3 |
comment |
How to check if a point is inside a rectangle? Wouldn't it be simpler, potentially fewer computations, and equally correct to test if the area of any triangle is greater than half the area of the rectangle? |
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Jun 5 |
awarded | Commentator |
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Jun 5 |
comment |
What is the chance to get a parking ticket in half an hour if the chance to get a ticket is 80% in 1 hour? A Markov chain is a much better assumption, since I've never heard of multiple tickets being issued to a car (that remains parked in one place) in the same day. Therefore "got 1 ticket" is a terminal state, there is no chance of moving to two tickets. The problem stated that there is an 80% chance of getting a ticket, not that the mean number of tickets is 0.8. Your answer confuses these two quantities. |
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Jun 4 |
comment |
What is the chance to get a parking ticket in half an hour if the chance to get a ticket is 80% in 1 hour? You've made a Markov assumption, which may or may not be valid. |
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Apr 27 |
comment |
How to prove that for $x$,$y$ positive if $x > y$, then $\frac{1+2x}{1+x} > \frac{1+2y}{1+y}$? @Arturo: The cross-multiplication step relies on the OTHER part of the postulate, that x+1 and y+1 are both positive. |
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Apr 26 |
comment |
How to prove that for $x$,$y$ positive if $x > y$, then $\frac{1+2x}{1+x} > \frac{1+2y}{1+y}$? The first step uses the postulate, that rather breaks "if and only if". |
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Oct 13 |
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Can I use my powers for good? @JackManey: Many American high schools are in such need of qualified math/science teachers that they're willing to forgo the "teaching certificate" and accept other credentials. |
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Mar 14 |
comment |
Both solutions to a quadratic make sense — looking for applications How about where the perimeter of three sides is fixed (classic question: Rectangular goat pen which abuts the side of the barn and using a fixed amount of fence for the remaining three sides)? That breaks the symmetry. |
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Feb 6 |
comment |
Fewest inequalities to define a hollow cube @Rahul: Thanks. I was thinking it would be a rotated cube, but you're right that it would have 8 faces and 6 vertices. |
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Feb 6 |
revised |
Fewest inequalities to define a hollow cube added 113 characters in body; added 2 characters in body; added 163 characters in body; added 4 characters in body |
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Feb 6 |
revised |
Fewest inequalities to define a hollow cube added 206 characters in body |
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Feb 6 |
awarded | Scholar |
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Feb 6 |
awarded | Supporter |
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Feb 6 |
accepted | Fewest inequalities to define a hollow cube |
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Feb 6 |
awarded | Editor |
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Feb 6 |
revised |
Fewest inequalities to define a hollow cube added 16 characters in body |
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Feb 6 |
comment |
Fewest inequalities to define a hollow cube No particular reason, I guess it could be described as math golf... but then many mathematical problems are. And I'm remembering that the $\max$ function can be implemented as a limit of polynomials (definition of $\infty$-norm), so that's really cool. |
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Feb 6 |
asked | Fewest inequalities to define a hollow cube |
