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| bio | website | mpi-sws.org |
|---|---|---|
| location | Kaiserslautern, Germany | |
| age | 31 | |
| visits | member for | 1 year, 2 months |
| seen | 2 hours ago | |
| stats | profile views | 286 |
PhD student at MPI-SWS.
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May 15 |
comment |
Complex Analyisis: Exponential Function Note that $e^{a+ib} = e^a (\cos b + i\sin b)$,hence $|e^{a+ib}| = e^a$. Do you know that $e^\cdot: \mathbb{R} \to (0, \infty)$? |
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May 15 |
comment |
Complex Analyisis: Exponential Function As said in my earlier comment, you will only be able to show that $e^\cdot: D \to \mathbb C \setminus \{ 0 \}$ is bijective, since $0$ is not in the image. |
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May 15 |
comment |
Complex Analyisis: Exponential Function In your notation, does one-to-one mean injective or bijective? In the latter case, this is not true: 0 is not in the image of the complex exponential function. |
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May 14 |
answered | Solve a cubic polynomial given that one root is four times a second root? |
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May 11 |
answered | Is it possible to divide n in d parts where each part can have a specific range of values? |
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May 11 |
revised |
Probability of gaining more than $\$20$ in a two person die game Layout |
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May 7 |
awarded | Caucus |
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May 7 |
answered | Infinite irrational number sequences? |
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May 2 |
answered | Computational Complexity of Algorithms |
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Apr 24 |
comment |
how discrete mathematics is related to computerscience Just as an example: Graph Theory, as an area of discrete mathematics, is used all over the place. Since you mention complexity, it is interesting to note that many graph-theoretic problems are natural examples of NP-complete problems. |
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Apr 5 |
comment |
Riemann-Stieltjes Integral is Everywhere Zero Hint: Use the fact that $f$ is not just integrable, but continuous. In particular, if there is some $x$ such that $f(x) > 0$, there is also an interval $I$ with $x \in I$ such that $f(y) > 0$ for all $y \in I$ (similar for $f(x) < 0$). |
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Mar 28 |
awarded | Good Answer |
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Mar 18 |
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What is true for a ring with exactly two right ideals As an example for a ring that satisfies II, but not I, consider the quaternions. For a finite ring that satisfies the property, take any finite field (e.g., $\mathbb Z/2Z$. As for proving II, I guess it should not be too hard to adapt the standard proof that a commutative ring with exactly two ideals is a field. |
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Mar 16 |
comment |
Regular Languages Algorithm? You're almost there. Do you know the algorithm for computing the product of two automata? |
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Mar 12 |
comment |
Monomial ordering deglex It is, in fact, that easy. |
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Mar 5 |
awarded | Yearling |
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Mar 2 |
comment |
Solving Differential equation with laplace transformation Hello and welcome to math.stackexchange.com. Since you are new here, I'd like to point out two things: 1. People don't like being addressed with imperatives here; please reformulate your question into an actual question format. 2. It's considered polite to describe not just the problem you are trying to solve, but also what you have tried and where you are stuck. This is particularly true if the question you ask stems from a homework problem (in which case it is also recommended to use the "homework" tag). About the question: Do you have a table of standard Laplace transforms available? |
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Mar 2 |
comment |
Not a Zero Divisor While it is true that $x-x=0$, this is not what was asked here. Also, note that we are talking about general rings and not numbers: The notion $b>c$ might not even make sense in the given ring. For example, in $\mathbb Z/2\mathbb Z$, there is no ordering compatible with addition. |
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Mar 2 |
comment |
Is there a notation for $f(x,y) - f(y,x)$? @vrich: And what does that have to do with the question? |
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Mar 1 |
answered | Correct notation or operator to remove elements from sequence |
