Sep
25
comment Arrangement of 5 letter words
Why $26 \cdot 25 \cdot 24 \cdot 25 \cdot 26$?
Sep
24
comment Another question on a 2-player game strategy
What have ypu tried?
Sep
23
comment Cardinal numbers of Setminus
2: follows from 1., at least if |.| is finite for all sets.
Sep
21
comment Algorithms - Induction (packing cups into boxes)
"Put all the cups of one color in a box..." If there are more than n cups of this colour than you will have still k colours left.
Sep
21
comment Good book for self-studying Binary Relations
The preface does not require an abstract algebra course that focuses mainly on binary relations but the binary relations material contained in the first weeks of an undergraduate abstract algebra course.
Sep
20
comment This is the question about integration. I want to know how to approach this question.
this is you 5th question. You should post your question formatted with LaTeX.
Sep
20
comment Proof of big-O notation
what doe you have to proof? how is $f(n)=O(n^{d})$ defined ?
Sep
20
comment What are some interesting cases of $\pi$ appearing in situations that are not / do not seem geometric?
$+1$ for $\pi_1$
Sep
20
comment Help with finding the real zeros of a polynomial
sorry, now we have wasted the saved time and space anyway.
Sep
20
comment Help with finding the real zeros of a polynomial
$(x+1),(x-1),(x+2),(x-2),(x+4),(x-4)$ are not the possible zeros of the polynomial, they are possible divisors or linear factors of the polynomial. Th possible zeros are $+1,-1,+2,-2,+4,-4$.
Sep
17
comment How to calculate running time of code?
-1 One way to solve the problem is only mentioned in two sentences. It doesn't answer the question becuase it does not show how to calculate the formulas. I don't think that one can derive a 4th degree polynomial by looking at your patterns
Sep
16
comment Proving a limit with epsilon delta definition
I don't understand what you mean by "f(x)=L+- ε 2=(1/2+-ε)x + 1 x= 3+- 2/ε". can you state in your post using the $\varepsilon$-$\delta$ notation what you have to prove?
Sep
12
comment Negation of a proposition of the form “not(p) & q”
yes, I think this is correct
Sep
12
comment Negation of a proposition of the form “not(p) & q”
If that what you expressed in English is "p & not(q)" then it is wrong because you have to express "p | not(q)". I think you have actually expressed "p & not(q)", so it is wrong.
Sep
12
comment Negation of a proposition of the form “not(p) & q”
not( not(p) & q) <=> (p | not(q)) or better $$\neg(\neg p \land q) \Leftrightarrow ( p \lor \neg q) $$
Sep
12
comment Showing Surjectivitity of $f(x) = x^3$
but then you should mention that it is countinous if this is a premise for you conclusion
Sep
12
comment coin problem with two coins, inductive proof
If you want somebody to discuss your proof it would be easier if you number your equation/inequations. I think you made a mistake, you cannot get $pab-pa-b \ \neq \ mpa + b(na+p-1)$ from the former equation. it should be $pab-pa-b \ \neq \ npa + b(mp+p-1)$ Also you should make your naming of variables consistent In the first part you use $n$ for the multiplier of $a$ int he second part you use $m$. This makes it more difficult to read the proof.
Sep
10
comment Proof of special case of Fermat's Last Theorem
The title is really bad. It does not say anything about the mathematicl content of the post.
Sep
10
comment Proof of special case of Fermat's Last Theorem
+1 I read it after the 3rd edit and it looks very clear and right for me.
Sep
9
comment Are there any mathematics “problem websites” similar to Project Euler?
This contains programming puzzles and challenges. There I found a link to ponder this. The current puzzle is a math problem. and i needed programming to find a solution of the current problem. Pen and Paper problems can be found on (imo-official.org/problems.aspx). Books about algorithms, number theory or numerical mathematics may contain the type of problems you are looking for