User hkBattousai - Mathematics Stack Exchange

bio	website	stirve.com
	location	Turkey
	age	33
visits	member for	1 year, 5 months
	seen	2 days ago
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	725 reputation	bio	website	stirve.com	visits	member for	1 year, 5 months
213 badges		location	Turkey		seen	2 days ago

8

votes

2

answers

121

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Solving matrix equations of the form $X = AXA^T + C$

may 17 at 7:28 Landscape 7,720

5

votes

2

answers

129

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Could we show $1-(x-\dfrac{x^3}{3!}+\dfrac{x^5}{5!}-\dots)^2=(1-\dfrac{x^2}{2!}+\dfrac{x^4}{4!}- \dots)^2$ if we didn't know about Taylor Expansion?

trigonometry power-series

apr 27 at 16:07 mercio 11.3k

4

votes

2

answers

1

kviews

What is the proof that covariance matrices are always semi-definite?

probability matrices vector-spaces proof-writing vector-analysis

mar 11 at 23:43 hkBattousai 725

1

3

votes

2

answers

131

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Probability of two buses being in a bus stop at the same time

probability probability-theory

feb 23 at 19:36 Adam Bailey 391

3

votes

1

answer

50

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What is the method of solving an equation set in which the unknowns are in denominator?

problem-solving

sep 6 at 9:59 Ralph Tandetzky 511

2

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3

answers

354

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Forming equation of a plane by solving linear equation set

geometry matrices intuition

may 17 at 5:57 Landscape 7,720

2

votes

1

answer

69

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What is the analytic expression for PDF of joint distribution of two Gaussian random vectors?

probability probability-theory multivariable-calculus probability-distributions normal-distribution

mar 18 at 6:26 Stefan Hansen 8,543

2

votes

0

answers

124

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Derivation of the density function of product of two random variables

probability probability-distributions proof-writing

jan 19 at 11:46 KCd 5,920

1

2

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3

answers

278

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Finding location of a point on 2D plane, given the distances to three other know points

algorithms circle

jan 19 '12 at 19:57 draks ... 6,328

1

vote

2

answers

45

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How do I factorize equations of the form $x^2 + Bxy + Cy^2 = 0$

algebra-precalculus factoring

may 7 at 11:44 André Nicolas 161k

1

vote

1

answer

29

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Discrete Time Fourier Transform example: $x = [1 \; 2 \; 3 \; 4]^T \; \rightarrow \; X=?$

fourier-analysis transformation

may 3 at 20:38 hkBattousai 725

1

vote

1

answer

35

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Can we write $\sqrt[w]{z}=z^\frac{1}{w}$ when both $w$ and $z$ are complex numbers? [duplicate]

notation complex-numbers powers

apr 27 at 12:53 somaye 1,943

1

vote

4

answers

71

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Complex power of a complex number: Find $x$ and $y$ in $x + yi = (a + bi)^{c+di}$

complex-numbers powers

apr 27 at 12:04 hkBattousai 725

1

vote

4

answers

169

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What exactly are the “higher order terms” (H.O.T.) in Taylor series expansion in multivariable case?

multivariable-calculus taylor-expansion

apr 19 at 15:58 Community♦ 1

1

vote

1

answer

52

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Expected value of a multivariate distribution

probability-theory multivariable-calculus average random-matrices

mar 19 at 19:35 Michael Hardy 48.2k

1

vote

1

answer

60

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Linear transformation applied to a multivariate Gaussian random variable - what is the mean vector and covariance matrix of the new variable?

linear-algebra multivariable-calculus normal-distribution random-variables

mar 17 at 18:21 Martin 3,688

1

vote

1

answer

60

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Calculating determinant of a matrix whose non-zero elements are two sub-matrices on its diagonal

matrices determinant

mar 17 at 16:43 Gigili 3,153

1

vote

2

answers

86

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Find $ \sum \limits_{k=1}^{\infty} k q^{k-1} \,\,$ when $\,\, 0 < q < 1 $ [duplicate]

sequences-and-series summation

jan 31 at 15:37 lab bhattacharjee 28.8k

1

vote

2

answers

2

kviews

What is the general formula for calculating dot and cross products in spherical coordinates?

inner-product-space spherical-coordinates cross-product

nov 24 at 1:13 James S. Cook 2,761

1

vote

2

answers

172

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Solution of Diophantine equation for polynomials

algorithms polynomials diophantine-equations

feb 26 '12 at 23:11 Gerry Myerson 85.9k

1

vote

1

answer

661

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What is the fastest numeric method for determinant calculation?

matrices numerical-methods determinant

dec 22 '11 at 16:57 user17762 76.3k

0

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3

answers

26

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Show that the maximum of a set of convex functions is again convex

convex-analysis

apr 26 at 7:58 hkBattousai 725

0

votes

2

answers

46

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Transpose of matrix inverse: $(AA^T)^{-1}A^Tb \stackrel{?}{=} (A^TA)^{-1}A^Tb$

matrices optimization derivatives inverse

apr 25 at 8:46 peterm 176

0

votes

0

answers

17

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Is $f_{\Theta|Z}(\theta|z)$ Gaussian when $Z = \theta^3 + V$, and given that $\Theta$ and $V$ are Gaussian?

normal-distribution transformation random-variables

apr 14 at 19:33 hkBattousai 725

0

votes

0

answers

47

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Finding marginal distribution from joint distribution when domain of one variable is given in terms of the other variable

multivariable-calculus integration probability-distributions solution-verification

apr 2 at 18:56 hkBattousai 725

0

votes

1

answer

44

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What is the correlation function in multivariable/vectoral case?

statistics multivariable-calculus random-variables correlation

mar 31 at 18:32 Caran-d'Ache 1,085

0

votes

1

answer

53

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How is conditional density function with two given conditions ($f_{X\mid Y,Z}(x\mid y,z)$) defined?

probability-theory probability-distributions random-variables conditional-probability

mar 25 at 18:24 hkBattousai 725

0

votes

2

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35

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How do you explain $f(x_4|x_3)f(x_3|x_2)f(x_2|x_1)f(x_1) = f(x_4,x_3,x_2,x_1)$?

probability-distributions proof-strategy markov-process

mar 23 at 8:22 pengsun.thu 73

0

votes

0

answers

51

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What are the $\succ$ and $\prec$ operators for when used with matrices?

matrices notation

feb 27 at 0:12 Willie Wong♦ 30.7k

0

votes

1

answer

31

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Solution of $ y'' + NK\frac{y'}{t_f-t} + NK^2\frac{y}{(t_f-t)^2}=0 $

homework differential-equations

dec 20 at 3:00 Juan Simões 251

hkBattousai

34 Questions