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8h
comment Does the sequence is convergent?
I didn't say that I think that you have not put in any effort. I said you showed no sign of effort --- that's very different. I also warned you that by showing no sign of effort you ran the risk of having your question closed. You chose to ignore my warning, and guess what --- I was right!
9h
comment An extension of an algebraic question from my test
How does the proof go for two matrices? Does the proof generalize?
12h
comment Algebraic Integers in $\mathbb{Q}(\sqrt{m})$ and Norms on them
@Adam, I don't think Niven's book discusses such things as the index of an ideal.
12h
comment How to prove $ \frac{e^{x}+e^{-x}}{2} \le e^{\frac{x^2}{2}} $?
They're both even functions, so it suffices to do $x\ge0$. First prove left side is bounded by $e^x$, then prove $e^x$ less than right side for $x>2$. Well, that still leaves $0\le x\le2$ for you to think about.
12h
comment Does the sequence is convergent?
You've been here long enough, Fisiai, to know that unsourced, undigested, copy-pasted questions showing no sign of effort are liable to get closed.
12h
comment Solving a simple Recurrence in summation form(very special case)
What you have is not a recurrence. There are any number of solutions. For example, you could let $f(3)=(2/3)(C-2c)$, $f(n)=0$ for $n\ge4$.
12h
comment Lower bound for a relative of the central binomial coeff
Have you tried to mimic a proof of the bound for the central binomial coefficient?
15h
comment Graphs and Trees: discrete math
Please don't dump unsourced, undigested problem here with no sign of any effort beyond what's needed to do a cut'n'paste. Tell us what you know about the problem, how far you get toward solving it, what particularly puzzles you, and so on. Do you understand all the vocabulary in the problem?
15h
comment Algebraic Integers in $\mathbb{Q}(\sqrt{m})$ and Norms on them
The integers of ${\bf Q}(\sqrt5)$ are not of the form $a+b\sqrt5$ with $a,b$ integers. $(1+\sqrt5)/2$ is an algebraic integer.
15h
comment Bisector of a triangle
Let me encourage you to write up your solution and post it as an answer. The more good answers the site has, the better.
1d
comment Minimizing sum of functions implies minimizing their squares, maximizing the sum of the inverses?
Any thoughts on the answer I posted 2 days ago?
1d
comment Rational Series VS Algebraic Series
Done, yesterday. Helpful now?
1d
comment Diophantine Equatiοn $x^3=2^y+15$
So, it's an exercise in the book? What book? What page? What context? Sometimes, it helps to know these things, they give clues as to the intended method of solution.
1d
comment Diophantine Equatiοn $x^3=2^y+15$
Why the interest in that particular equation?
1d
comment How to find factors when factoring
"...when trying to factor slightly higher primes such as 17 or 31." Factoring primes is trivial. What you meant was, finding slightly higher prime factors. If you're going to teach, I beg you to say to your students exactly what you mean, and not something sorta kinda like what you mean. They will find the mathematics hard enough, without having to decipher sloppy statements of problems, definitions, solutions, and so on.
1d
comment Miscellaneous questions about trees
If you think (2) is wrong, you ought to be able to produce such a tree with height 4. Can you?
1d
comment Exponential irrationality
Chances are, your number has irrationality measure 2 --- almost all number do --- but I doubt there's a proof known for your number.
1d
comment dynamics in a group
Are you at a university? Does it have a Math Department? Is there someone there you can talk to? You'll probably get better advice from someone who knows you than from a bunch of strangers.
1d
comment Exponent calculation
The way to calculate $10^x$, given $x$, is to use a calculator.
1d
comment Quadratic congruence with composite; $ x^2\equiv\ 31\ ({\rm mod}\ 11^4)$
If you think 47 is large, you are not going to enjoy Number Theory. $11^4=14641$, so there's every reason to expect the final answer to have 4 or 5 digits.