114,979 reputation
7106212
bio website von-eitzen.de/math/tntrep.xml
location Bonn, Germany
age 48
visits member for 2 years, 1 month
seen 5 hours ago

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


Oct
22
answered Equivalent Statement of Chain Rule
Oct
22
comment 8 questions on true/false quiz. Expected number of correct answers with a given probability of correct answer of a question “i”.
@satishramanathan That's a complicated way of computing the reuslt. Seeing that expectations can simply be added, makes the computation much simpler. Moreover, the problem statement does not say that the events are independant; hence your proposed method may not be adequate. Additivity of expectations does not need independence.
Oct
22
comment What is and what represents a convergents function in polynomial form?
@user2485710 In a way the convergents are the best possible rationl approximations. It's no surprise that the well-known approximations $3$ and $\frac{22}7$ are emitted as the first convergents for $\pi$, for example
Oct
22
comment What is the opposite category of $Set$?
In other words, recall that a morphism from $A$ to $B$ in $\textbf{Set}^{op}$ is nothing else but a function $B\to A$.
Oct
22
comment Prove By Induction (Fibonacci Sequence)
@Ron.J.Adams By applying any of the definitions of $\gcd$ or one step of the Euclidean algorithm
Oct
22
answered What is and what represents a convergents function in polynomial form?
Oct
22
answered Prove By Induction (Fibonacci Sequence)
Oct
22
comment 8 questions on true/false quiz. Expected number of correct answers with a given probability of correct answer of a question “i”.
@DavidP. That was meant to reflect the definition of expected value $E(X)=\sum_k x_k(P(X=x_k)$ more properly, here with $P(X=1)=p$ and $P(X=0)=1-p$.
Oct
22
answered 8 questions on true/false quiz. Expected number of correct answers with a given probability of correct answer of a question “i”.
Oct
22
reviewed Reviewed 8 questions on true/false quiz. Expected number of correct answers with a given probability of correct answer of a question “i”.
Oct
22
revised 8 questions on true/false quiz. Expected number of correct answers with a given probability of correct answer of a question “i”.
deleted 90 characters in body
Oct
22
comment sign of roots of a quadratic equation with complex coefficients.
@Nilan $-a$ is the sum of the two roots, hence $\Re a>0$ is necessary.
Oct
22
comment How can I prove the existence of an octagon/decagon/dodecagon?
dodecahedron or dodecagon?
Oct
22
comment Proof of Soundness Lemma
The induction variable hides elsewhere, though: For a given $\Gamma$-proof, show that $\bar\nu(\phi_k)=T$ for all $k\le n$
Oct
22
comment The product of uniformly continuous functions is not necessarily uniformly continuous
"If I attempt to prove $X$, the proof gets hairy" is not a valid method to prove $\neg X$.
Oct
22
answered Calculating the Growth of A Small Population After 1000 Years
Oct
22
comment Calculating the Growth of A Small Population After 1000 Years
100 people at what age? Babies for simplicity?
Oct
22
answered Clarification on proof that all groups of order $< 60$ are solvable
Oct
22
answered How to factor $x + 1 - 2 \sqrt x$?
Oct
22
revised How to factor $x + 1 - 2 \sqrt x$?
edited title