Dan Piponi
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 Dec 3 comment Approximate solutions for quintic equation Nov 14 awarded Necromancer Nov 12 comment Cardinality of infinite sets - Help with intuition "why can't I do the exact same thing when dealing with the mapping between odds/integers?" Have you tried? Nov 7 comment Function 'result arity' In my many years of mathematics I've never come across such a term. Oct 26 answered Simplifying expressions when taking limit to infinity Sep 18 revised why binary is read right to left added 12 characters in body Sep 18 revised why binary is read right to left added 12 characters in body Sep 18 answered why binary is read right to left Aug 25 answered Does $G$ always have a subgroup isomorphic to $G/N$? Aug 13 comment If $P(A) = 0$ is $A$ a null event? @user159813 The fact that the "event is a non empty set" does not make the event "non-null". The set of pairs of integers that sum to 13 is non-empty but it's impossible to roll 13 with two ordinary dice. Aug 5 comment In calculus, which questions can the naive ask that the learned cannot answer? First, you don't need table look-ups to compute elliptic integrals. There are a variety of methods for computing them. Second, in what sense can you not exactly calculate the arc-length of an ellipse but can exactly calculate the arc-length of a circle? Aug 4 comment using the same symbol for dependent variable and function? This is a problematic area. Despite functions playing a central role in much of mathematics there isn't a clear unambiguous notation that mathematicians agree on. I think a good modern view is that $y$ is a function and $y(t)$ is the value of the function evaluated at $t$ in which case it (usually) makes no sense to say $y=y(t)$. But others take the view that $y=y(t)$ is a special use of notation that emphasises that $y$ is a variable that depends on $t$ and so is perfectly acceptable. Aug 4 revised Computing the sum of an infinite series The sum is not the same as the series itself Aug 4 suggested approved edit on Computing the sum of an infinite series Jul 29 answered Examples of “Non-Logical Theorems” Proven by Logic Jul 24 comment Can universal instantiation be used more than once? If technique X can only be used once in a proof, and I use it to prove A implies B, and use it to prove B implies C, then I wouldn't be able to combine these proofs to show A implies C as that would require two uses, and mathematics would pretty well come to a halt. Jul 20 awarded Yearling Jul 14 comment Why is the height of a heap defined as $\lg n$? See mathworld.wolfram.com/Lg.html for some discussion of what the notation $\mathop{lg}$ (as opposed to $\log$ or $\ln$) means. Jul 14 comment Are the real numbers really uncountable? I'm not sure what the issue is @frogeyedpeas . When a mathematician says "there exists an x such that..." they're not saying "there exists an x, with definition Y, such that...". If you want to, you can study numbers with this property but that has no bearing on the existence of the other numbers. Jul 14 awarded Nice Answer