92,210 reputation
581169
bio website von-eitzen.de/math/tntrep.xml
location Bonn, Germany
age 48
visits member for 1 year, 7 months
seen 3 hours ago

I did study math and had a knack for it, but I am sooo out of that business now ...


3h
comment Every integer greater than 1 is divisible by at least one prime. Can anyone please express this in logical notation
Do you have predicates for "is integer", "is greater than", "divides", "is prime" and a constant symbol for "1" available?
3h
answered Exercises in combinatorics
3h
comment Exercises in combinatorics
Where do cycles come from in 3)?
3h
comment Irrationality of $\pi$ and circumference to diameter ratio.
Note that $\frac13$ also has "never ending numbers after decimal". This doesn't contradict the fact that $\frac13$ is finite.
3h
answered Explain “There is a unique function from $\emptyset$ to any set $A$”.
4h
answered How would Intermediate Value Theorem be used in this question?
4h
revised How would Intermediate Value Theorem be used in this question?
added 8 characters in body
15h
comment exercise involving exactness
I assume here monomorphism only means left-cancelable?
15h
answered Regular Expressions Help
15h
comment prove that commuting ring is a subring of E(M) .
$E(M)$ is a ring with pointwise addition as addition and composition as multiplication. But that is in general not commutative.
15h
comment Application of computers in higher mathematics
Actually, a mathematican would often rather observe some interesting properties and from them go back to look for suitable axioms :)
15h
comment Closed form questions
Can you somehow describe the pattern and values o fthese sequences in words? Do you have a closed form for $+1,-1,+1,-1,+1,-1,\ldots$?
15h
comment If $a^2+b^2=1$ where $a,b>0$ then find the minimum value of $(a+b+{1\over{ab}})$
Well stat looks a lot like caclulus
16h
comment cardinality with finite sets
You do use transitivity, but to conclude $A\subseteq C$.
16h
comment A question about entire function.
There is an even more elementary solution, not to say trivial ... Btw., how do you find entire functions with poles?
16h
answered Proof that the coefficients of a polynomial are real
16h
answered Defining operations for a vector space
16h
answered How to solve for $f(2)$ given $3f(x)+f(2-x) = 2x^2$?
17h
comment How to solve for $f(2)$ given $3f(x)+f(2-x) = 2x^2$?
Just write down the equation again, but replace each occurance of $x$ with $0$. Then write down the equation again, but replace every occurance of $x$ with $2$. Then simplifiy what can be simplified (e.g. $2-2$ becomes $0$, $2^2$ becomes $4$, ...)
17h
answered Proof that in any base, the sum of two numbers of fixed precision can't have carry more than 1