User ghshtalt - Mathematics Stack Exchange

bio	website
	location
	age
visits	member for	2 years, 6 months
	seen	Mar 10 at 19:08
stats	profile views	134

	852 reputation	bio	website		visits	member for	2 years, 6 months
2619 badges		location			seen	Mar 10 at 19:08

10

votes

2

answers

904

views

Show that the set of all symmetric, real matrices is a subspace, determine the dimension

linear-algebra

may 8 '12 at 14:31 rschwieb 21.1k

10

votes

2

answers

1

kviews

Determine the matrix relative to a given basis

linear-algebra matrices

nov 29 '10 at 21:01 Arturo Magidin 158k

1

9

votes

8

answers

842

views

Showing that an equation holds true with a Fibonacci sequence: $F_{n+m} = F_{n-1}F_m + F_n F_{m+1}$

discrete-mathematics fibonacci-numbers

dec 24 '10 at 22:01 Mike Spivey 25.9k

3

8

votes

1

answer

237

views

What is the difference between finding a basis for a complex and a real space?

linear-algebra

apr 23 '11 at 20:28 Arturo Magidin 158k

2

8

votes

1

answer

987

views

How are norms different from absolute values?

norm

jan 2 '11 at 22:39 Arturo Magidin 158k

1

5

votes

3

answers

346

views

What are the explanations for certain steps in these proofs for the irrationality/rationality of certain numbers?

analysis

aug 19 '11 at 19:04 robjohn♦ 60k

2

5

votes

2

answers

259

views

Understanding this partial derivative problem

multivariable-calculus

jun 30 '11 at 22:09 Arturo Magidin 158k

5

votes

2

answers

523

views

Why is the 'change-of-basis matrix' called such?

linear-algebra

feb 13 '11 at 21:37 ghshtalt 852

1

5

votes

3

answers

212

views

Proving or disproving statements related to convergent and absolutely convergent series

analysis sequences-and-series

dec 2 '10 at 19:48 AD. 5,516

1

4

votes

1

answer

457

views

Showing properties of discontinuous points of a strictly increasing function

analysis

apr 11 at 18:28 Himadri Distant Tide 1

1

4

votes

2

answers

170

views

What is the explanation for the elements of this set?

elementary-set-theory

sep 8 '11 at 0:00 Srivatsan 15.6k

4

votes

3

answers

381

views

Why does $a_n = (1+\frac{2}{n})^{n}$ converge to $e^2$?

calculus

apr 21 '11 at 17:49 ghshtalt 852

4

votes

1

answer

162

views

Why is this tuple of vectors not a basis for $\mathbb{R}^{2}$?

linear-algebra

jan 25 '11 at 16:12 Arturo Magidin 158k

4

votes

2

answers

465

views

Step functions and the characteristic function of rationals

analysis

jan 5 '11 at 22:39 Aryabhata 47.7k

3

votes

5

answers

1

kviews

Proving $(2n+1) + (2n+3) + \cdots + (4n-1) = 3n^{2}$ for all positive integers $n$

induction

mar 10 at 19:11 ghshtalt 852

3

votes

2

answers

238

views

Why exactly can you take the absolute value of one side of this inequality and assume it is still true?

absolute-value

sep 22 '11 at 17:30 Tomas 272

3

votes

1

answer

107

views

Are bounded sequences always strictly less than some fixed number $M$?

sequences-and-series

may 14 '11 at 15:49 Nate Eldredge 22.4k

3

votes

2

answers

129

views

How to show certain things related to scalar products

homework linear-algebra

apr 17 '11 at 20:03 ghshtalt 852

3

votes

1

answer

351

views

Determine sign of a permutation, calculate number of elements in the subgroup of permutations with sign = 1

homework group-theory permutations symmetric-groups

dec 15 '10 at 0:19 ghshtalt 852

3

votes

2

answers

185

views

Calculate the rank of the following matrices

linear-algebra matrices

dec 5 '10 at 23:36 Arturo Magidin 158k

2

votes

1

answer

85

views

For which $k \in \mathbb{R}$ will this be a euclidean vector space?

linear-algebra

jul 5 '11 at 12:02 Joel Cohen 3,669

2

votes

1

answer

113

views

Help understanding this example of a linear operator which rotates each vector $v$ about the z-axis by an angle $\theta$

linear-algebra

jul 3 '11 at 20:39 Jason DeVito 14.3k

2

votes

2

answers

185

views

What is the best way to show that no positive powers of this matrix will be the identity matrix?

linear-algebra

may 15 '11 at 13:44 ghshtalt 852

1

2

votes

1

answer

419

views

Who was the mathematician who thought “god” was out to get him?

math-history mathematicians

may 6 '11 at 20:56 Asaf Karagila 91.6k

2

votes

2

answers

425

views

Subtraction and division with integers modulo 3

finite-fields

apr 17 '11 at 8:12 Gerry Myerson 86k

1

2

votes

1

answer

149

views

How do you convert this diagram into a linear system of equations/matrix form?

homework puzzle

jan 31 '11 at 17:28 Arturo Magidin 158k

2

votes

1

answer

2

kviews

How to calculate complex roots of a polynomial

polynomials

jan 11 '11 at 19:29 Arturo Magidin 158k

2

votes

3

answers

252

views

Show that $V = \mbox{ker}(f) \oplus \mbox{im}(f)$ for a linear map with $f \circ f = f$

linear-algebra

nov 27 '10 at 21:30 user3180 1,217

2

votes

1

answer

207

views

Proving statements related to open sets

analysis general-topology

nov 25 '10 at 19:31 Arturo Magidin 158k

1

vote

5

answers

2

kviews

Show that a continuous function has a fixed point

analysis

dec 20 at 1:41 mixedmath♦ 27.3k

ghshtalt

41 Questions