User Gamecocks99 - Mathematics Stack Exchange

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	305 reputation	bio	website		visits	member for	4 months
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5

votes

2

answers

43

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Let G be a group and let $a\in G$. Define $F_a:G\mapsto G$ via $F_a(x)=axa^{-1}$ for all $a\in G$. Prove that $F_a$ is an isomorphism from G onto G

apr 24 at 5:41 Babak S. 28k

3

votes

3

answers

76

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Given the differential equation $(1+t^2)dy/dt+4ty=(1+t^2)^{-2}$

differential-equations

jan 28 at 16:24 Did 103k

3

votes

0

answers

101

views

Which sets sets of natural numbers are closed under addition? [duplicate]

abstract-algebra number-theory

jan 24 at 22:41 Ross Millikan 83.6k

1

2

votes

1

answer

46

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Let G be a finite group and let H and K be subgroups of G. Suppose [G:K] and [G:H] are relatively prime. Prove G=HK [duplicate]

group-theory finite-groups

may 3 at 20:19 vadim123 8,286

2

votes

2

answers

153

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Use Method of Undetermined Coefficients to find general solution

differential-equations

apr 29 at 20:42 FreshDresch 77

2

votes

2

answers

59

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Principal Ideal Domain

abstract-algebra ring-theory ideals

apr 24 at 22:03 Community♦ 1

2

votes

2

answers

31

views

Show that $(1-\frac{1}{n})^{\sum_{i=1}^{n} X_i}$ is an unbiased estimator of $\tau(\theta)=e^{-\lambda}$

statistics statistical-inference

apr 23 at 3:19 Christopher Ernst 703

2

votes

2

answers

83

views

Solve the differential equation $\dot x=Ax$

differential-equations

apr 7 at 3:47 Artem 2,558

2

votes

1

answer

63

views

Roots to Homogeneous DE $y^{(4)}-y=0$

differential-equations

mar 5 at 20:40 Cortizol 1,316

2

votes

2

answers

94

views

Differential Equations: Population Problem $dp/dt= 0.5p - 380$

homework differential-equations

jan 27 at 23:17 Amzoti 14.1k

1

vote

2

answers

44

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Let H and K be subgroups of the finite group G and supposes $|H|^{2}>|G|$ and $|K|^{2}>|G|$. Prove $H \cap K$ has at least two elements

group-theory finite-groups proof-writing

may 4 at 2:18 Easy 2,567

1

vote

1

answer

26

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Let $X_1,\ldots,X_n$ be IID from EXP($\lambda=1/ \theta$) so $E[X_1\mid\theta]=\theta$. Use MGF technique to find distribution of $\sum_{i=1}^{n} X_i$

statistics probability-distributions

apr 25 at 4:22 Michael Hardy 48.3k

1

vote

1

answer

30

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Let G be a finite group and let H and K be a subgroup of G so that [G:K] and |H| are relatively prime. Prove that [G:K]|H| divides |G|

abstract-algebra group-theory finite-groups

apr 24 at 4:02 Patrick McLaren 117

1

vote

3

answers

37

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G is a group, H is a subgroup of G, and N a normal group of G. Prove that N is a normal subgroup of NH.

abstract-algebra group-theory

apr 14 at 17:00 Serkan 3,099

1

vote

1

answer

20

views

How to interpret these regression values?

homework regression

mar 26 at 3:08 Michael Hardy 48.3k

1

vote

4

answers

69

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Prove the following about $S_n$ and $A_n$

abstract-algebra group-theory symmetric-groups

mar 25 at 10:52 azimut 5,508

1

vote

2

answers

86

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Find the solution of the given initial value problem $y^{(4)}-4y'''+4y''=0$

differential-equations

mar 5 at 1:16 Jack 7,521

1

vote

0

answers

24

views

Test the hypothesis that $B_1=0$ at the $5 \%$ significance level

homework statistical-inference

feb 17 at 18:47 Diego Silvera 917

1

vote

2

answers

79

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Let $R$ be any ring. Prove that the following equations must hold in $R$.

homework abstract-algebra ring-theory

feb 9 at 8:37 Robert 790

1

vote

2

answers

65

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Permutation and Equivalence

abstract-algebra

feb 4 at 15:36 amWhy 55.2k

1

vote

2

answers

57

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Permutations and Equivalence Relations

elementary-set-theory equivalence-relations

feb 4 at 0:05 Asaf Karagila 91.5k

1

vote

1

answer

58

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$ y=y_1(t)+y_2(t)$ is solution of $y'+p(t)y=g(t)$ if $y=y_1(t)$ is one of $y'+p(t)y=0$ and $ y=y_2(t)$ is one of $y'+p(t)y=g(t)$

differential-equations

feb 1 at 6:08 Community♦ 1

1

vote

3

answers

49

views

$y'=(8\cos8x)/(3+2y)$ with $y(0)=-1$ Initial Value Problem: DiffEq

differential-equations

jan 26 at 4:57 Mhenni Benghorbal 14.2k

1

vote

3

answers

108

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Is the function $f:\mathbb{R}^2\to\mathbb{R}^2$, where $f(x,y)=(x+y,x)$, one-to-one, onto, both?

functions elementary-set-theory

jan 25 at 11:47 Stefan Hansen 8,583

0

votes

1

answer

32

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Let $h$ be a homomorphism from A onto B, $g$ a homomorphism from A onto C such that $ \ker g\subset \ker h$. Prove there's a homo. $f$ from B onto C

abstract-algebra

may 4 at 14:05 learner 2,001

0

votes

0

answers

28

views

What is a topic I could easily collect data on that follows a poisson distribution?

statistics probability-distributions statistical-inference

apr 16 at 11:29 Gamecocks99 305

0

votes

1

answer

37

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$GL(3,\mathbb R)/SL(3,\mathbb R)$ is isomophic to $\mathbb R^\times$

abstract-algebra group-theory

apr 14 at 20:22 YACP 9,190

0

votes

1

answer

57

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If G is a finite group, and $\exists !$ $H\leq G$ such that $|H| =n$, then $H \triangleleft G$.

abstract-algebra group-theory finite-groups

apr 14 at 15:44 amWhy 55.2k

0

votes

0

answers

40

views

Omitted Variable Bias?

homework regression economics

mar 26 at 0:44 Gamecocks99 305

0

votes

3

answers

43

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R is an integral domain with p in R and p not equal to 0 and if p|ab than p|a or p|b. Prove that p is irreduciable.

abstract-algebra

mar 4 at 3:22 Community♦ 1

Gamecocks99

42 Questions