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Markov inequality for $|X-EX|^4$.

probability

answered 5 mins ago Henry 69.9k

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Evaluate $\lim_{x\to 0}\left ( \frac{1}{\ln(x+\sqrt{1+x^2})}-\frac{1}{\ln(1+x)} \right )$

calculus limits logarithms radicals

modified 7 mins ago Martin Sleziak 36.8k

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Topology (connected sets)

general-topology

asked 8 mins ago user361170 9

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Verify whether or not a subset is a subspace of R3

linear-algebra vector-spaces subspaces

answered 14 mins ago mrf 32.4k

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If $\varphi:\mathbb{R}^2\rightarrow T$ is continuous and surjective, then $\varphi^{-1}(0,0)$ has infinitely many elements.

real-analysis general-topology contest-math

answered 15 mins ago mrka 393

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Are there multiple solutions to $P \ \cap J \ \cap \ C$ in this question?

probability statistics discrete-mathematics

asked 19 mins ago Perturbative 963

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Is $(7,4)$ the only non-trivial integer solution for $(n)_k=n!$?

combinatorics diophantine-equations factorial gamma-function pochhammer-symbol

answered 25 mins ago Batominovski 13.2k

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Show the quadratic function $W(x_1,x_2,\ldots,x_n)=A\sum_{i} x_i^2+ \sum_{i\neq j} x_ix_j$ is strictly quasi-concave

linear-algebra matrices functions convex-analysis determinant

modified 26 mins ago H. H. Rugh 5,635

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Mean Square Error Minimization Conditioned On Multivariate Normal Random Variables

probability multivariable-calculus normal-distribution conditional-expectation mean-square-error

modified 28 mins ago user3100463 6

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Lateral limits of an endpoint of the interval.

calculus real-analysis limits

modified 28 mins ago An old man in the sea. 939

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Field extension over the reals

abstract-algebra field-theory

answered 34 mins ago Eric Wofsey 57.1k

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Finding the value of an infinite trigonometric series

sequences-and-series algebra-precalculus trigonometry trigonometric-series

modified 37 mins ago DonAntonio 111k

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Is the centralizer of a Subgroup abelian?

abstract-algebra finite-groups

modified 42 mins ago mobzopi 550

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Prove that the given matrix has only one eigenvalue at 0

linear-algebra matrices pde eigenvalues-eigenvectors

answered 44 mins ago Ignat 416

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Markov inequality for $|X-EX|^4$.

Evaluate $\lim_{x\to 0}\left ( \frac{1}{\ln(x+\sqrt{1+x^2})}-\frac{1}{\ln(1+x)} \right )$

Topology (connected sets)

Verify whether or not a subset is a subspace of R3

If $\varphi:\mathbb{R}^2\rightarrow T$ is continuous and surjective, then $\varphi^{-1}(0,0)$ has infinitely many elements.

Are there multiple solutions to $P \ \cap J \ \cap \ C$ in this question?

Is $(7,4)$ the only non-trivial integer solution for $(n)_k=n!$?

Show the quadratic function $W(x_1,x_2,\ldots,x_n)=A\sum_{i} x_i^2+ \sum_{i\neq j} x_ix_j$ is strictly quasi-concave

Mean Square Error Minimization Conditioned On Multivariate Normal Random Variables

Lateral limits of an endpoint of the interval.

Field extension over the reals

Finding the value of an infinite trigonometric series

Is the centralizer of a Subgroup abelian?

Prove that the given matrix has only one eigenvalue at 0

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