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3h
comment Proof that $12$ in a row tic-tac-toe is a tie game?
@bof Mine is in two volumes also, but there is a new(er) edition by A.K. Peters in which the four parts (“Spade work”, “A change of heart”, etc.) are in four separate volumes.
1d
comment $\sim p$ ,$\sim\sim\sim\sim\sim p$ , and $\sim\sim\sim\sim\sim\sim\sim\sim\sim\sim\sim\sim p$ . Which of these are equal?
Yes, your answer is correct.
Apr
13
comment Determining Equation Based on Number Set
Your question is really unclear. Can you please give an example where you do know the answer, so that we can understand better what you are trying to do?
Apr
13
comment How many natural numbers less than $10^{2015}$ have their digits in non-decreasing order?
Hint: such a number is completely characterized by giving the number of leading 1s, then the number of following 2s, and so forth.
Apr
12
comment How to construct a DFA for truncate the rightmost symbol from a given string?
Maybe she's trying to make a Mealy machine.
Apr
12
comment how $1/0.5$ is equal to $2$?
Suppose you have 10 cookies and you want each kid to get 3 cookies. $10\div 3 = 3\frac13$. This means you have enough cookies for 3 kids, and only $\frac13$ of a full share for kid #4. Now suppose you have 1 cookie and you want each kid to get 2 cookies. $1\div 2 = \frac12$. This means you have enough cookies for 0 kids, and only $\frac12$ of a full share for kid #1.
Apr
11
comment No. of paths in a Table
sprunge.us/SVZL
Apr
11
comment How to read a cycle graph?
Thanks for pointing that out.
Apr
11
comment How to read a cycle graph?
It might be worth mentioning that the author of this diagram is notorious in the Wikipedia math community for assembling many complex, attractive diagrams that nobody else can easily understand.
Apr
11
comment Why every set of positive measure has non-measurable subsets
It's the contrapositive of the preceding theorem.
Apr
8
comment How to minimize $a \times b$ where $a^b≥x$?
(If nobody answers this, then I will later.)
Apr
8
comment How to minimize $a \times b$ where $a^b≥x$?
I suggest you change the title to something like "Minimize $ab$ where $a^b \ge N$”. Someone else will surely write up the answer, but this problem is easily solved by elementary differential calculus, and it would probably not take you very long to learn enough to solve it that way; calc textbooks are full of exercises that are very similar to your question. If you're interested, this would be a great place to start investigating calculus, which I encourage you to do, because you would probably enjoy it.
Apr
8
comment Is there an operation that takes $a^b$ and $a^c$, and returns $a^{bc}$?
That is the answer I wish I had written. Thanks for writing it.
Apr
8
comment How to prove that $2^\sqrt2$ is irrational
It is a consequence of the Gel'fond-Schneider theorem. If there is an elementary proof, I've never seen it.
Apr
7
comment Is there any other constant which satisfy Euler formula?
It holds for $-i$.
Apr
7
comment Counting Reals with the Lambda Calculus
You are exactly correct, the computable numbers are countable, for exactly the reason that you said. Relevant: Are there any examples of non-computable real numbers?
Apr
7
comment Is there an operation that takes $a^b$ and $a^c$, and returns $a^{bc}$?
Operators don't work that way.
Apr
7
comment Is there an operation that takes $a^b$ and $a^c$, and returns $a^{bc}$?
3 and 7 are two numbers with the same base.
Apr
7
comment Is there an operation that takes $a^b$ and $a^c$, and returns $a^{bc}$?
Zach: But $3 = 2^x$ and $7=2^y$ for certain $x$ and $y$, so you're saying that $2^x?2^y = 2^{xy}$, but also that $3?7 $ is undefined?
Apr
7
comment Is there an operation that takes $a^b$ and $a^c$, and returns $a^{bc}$?
@mark Maybe I was not answering the question you meant to ask. If this was what you were looking for, I'm glad.