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1h
comment can this decimal number be converted into a fraction?
The number can be written in terms of the Jacobi theta functions, as $2/3$ plus some rational multiple of $\vartheta_2(0;\sqrt{10})/\sqrt[8]{10}$.
1h
comment Calculating a formula for variables with multiple values equaling the same total
And what if $x$ is too small to match the $y$?
2h
revised Characterize magic matrices in terms of their eigenvalues. A Magic Matrix over a field $F$ is a square matrix whose row and colums sums $c\in F$.
added 1 character in body
2h
comment Characterize magic matrices in terms of their eigenvalues. A Magic Matrix over a field $F$ is a square matrix whose row and colums sums $c\in F$.
@José: Yes, that's what the "with the same eigenvalue" condition is for.
2h
revised Characterize magic matrices in terms of their eigenvalues. A Magic Matrix over a field $F$ is a square matrix whose row and colums sums $c\in F$.
note dependence on characteristic
2h
answered Characterize magic matrices in terms of their eigenvalues. A Magic Matrix over a field $F$ is a square matrix whose row and colums sums $c\in F$.
2h
comment Calculating a formula for variables with multiple values equaling the same total
x @ryan: What I'm saying that the function that always returns 100 no matter what $x$ and $y$ are satisfies everything you have required so far. If you want $x$ and $y$ to appear textually in the expression, you can write 100+0*x+0*y. If that does not satisfy your purpose, it must be because there is something you have not told in the question. Are there some input values where you want the result to be different from 100? Which inputs are that, and which output do you want there?
3h
answered rotation matrix and vector - understand step calculation
3h
revised Calculating a formula for variables with multiple values equaling the same total
edited tags
3h
comment Calculating a formula for variables with multiple values equaling the same total
You need to have some more requirements -- at present the constant formula 100 satisfies everything you have specified.
3h
comment rotation matrix and vector - understand step calculation
You need to have $\mathbf W_2=A\mathbf V_2$ too ...
5h
comment Why is $n^\sqrt n - 2^n \to - \infty$ and $\sqrt n ^n - 2^n \to +\infty$
In the first part we have an expression of the form $a^c-b^c$ where (eventually) $a>b>1$ and $c\ge 1$. In that case it is easy to see that $a^c-b^c \ge a-b$, so it is enough to prove that $a-b$ goes to infinity. The omitted step in the second part is the same, except with the opposite sign.
5h
revised Why is $n^\sqrt n - 2^n \to - \infty$ and $\sqrt n ^n - 2^n \to +\infty$
edited body
5h
answered Why is $n^\sqrt n - 2^n \to - \infty$ and $\sqrt n ^n - 2^n \to +\infty$
6h
revised Is a relation from a set $A$ to a set $B$ always a proper subset of $A\times B$?
escape the set brackets
6h
answered Is a relation from a set $A$ to a set $B$ always a proper subset of $A\times B$?
6h
revised Complex number, power series
edited tags
6h
revised Integral transformation
edited tags
6h
revised Orthogonal Projection in subspace
edited tags
6h
revised Rao-Blackwell theorem and conditional distribution
edited tags