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seen Sep 18 at 7:17

Sep
17
answered is growth of x+sin(x) same as x?
Sep
17
comment is growth of x+sin(x) same as x?
$x+sin(x) \in \Theta (x)$ which means that the growth is the same.
Sep
17
comment Proof that every number has at least one prime factor
Isn't this basically by definition? Either, a number is a prime number, then it is divisible by itself, or it is not a prime number, which means that it is divisible by a prime factor?
Sep
16
comment Do two data sets have the same distributions?
I think, if you put a little more effort in the question, this could be an interesting problem. What have you tried so far, what are your ideas?
Sep
15
comment Fibonacci sequence: Prove the formula $f_{2n+1}=f_{n+1}^2 + f_n^2$
The formula is derived here
Sep
15
comment Find point where radius of curvature is minimum
And do you know, how the curvature is defined?
Sep
15
comment Find point where radius of curvature is minimum
What have you tried so far?
Sep
15
comment Shared groceries expenses between roommates to be divided as per specific consumption ratio and attendance
The fact that I use different period accounts for the fact, that if somebody is there for a longer time, they possibly consume more food ( of course I still account for the percentage ).
Sep
15
comment Shared groceries expenses between roommates to be divided as per specific consumption ratio and attendance
No, that is not how I would calculate that. Assuming A and B consume $1/2$ each and are there for 50 days. Then the first period would be the time from day 1 to day 50 where everybody is there and that period would be weighted with 1, giving $1/2*1$ for A and $1/2*1$ for B. The second period is then weighted with zero.
Sep
14
comment Numerical analysis Taylor 1/(1-x)
You're correct. The error is decreasing if you increase the degree of your Taylor expansion. Additionally, the further you are away from the expansion point, the large the error.
Sep
14
revised Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
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Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
Simply use $f^j_n(x) = 1-\sqrt[n]{h^j(x)}$ with $h^j(x) = 1-\frac{1}{1-(x-j)^2}$. Then $h_j(j) = 0$ and $h_j(x)\not = 0$ for $x\not = j$ and thus $f$ is defined on $\mathbb{R}$.
Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
I'll try to come up with something for the floor function.
Sep
14
revised Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
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Sep
14
revised Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
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Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
Oh damn, no that is wrong, it is $1$ everywhere except for $x=0$, let me correct that.
Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
No this means that it is a sequence. And the fact that $f(x)=0$ for $0\leq x < 1$ is not by definition, but because the $n$th square root converges to exactly this if $n\rightarrow \infty$.
Sep
14
comment How to show $\log a\le n(\sqrt[n]{a}-1) \le \sqrt[n]{a}\log a$
You did not use your definition of $b$.
Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
@Masacroso in the example I provide, the sequence $f_n$ maps to $\mathbb{R}$ but in the limit $f$ maps to $\mathbb{N}$ is this what you are looking for?
Sep
14
comment Exist a function composed by simple continuous functions that $f:\Bbb R \rightarrow \Bbb N$?
You can extend the function to $\mathbb{R}$ instead of $[0,1]$ if you find a function $h_j(x)$ that has the property $h_j(j)=1$ and $0\leq h_j(i)<1$ when $i\not = j$. Then define $f_n^j(x) = \sqrt[n]{h_j(x)}$. This could for example be the Normal distribution with $\mu =j$ and normalizing $\sigma$.