User Abdu Magdy

7 votes

4 answers

730 views

Every infinite subset of $E$ in $\mathbb R^k$ having a limit point in $E$ implies $E$ is closed

asked Jan 12, 2018 at 20:27

3 votes

1 answer

2k views

What are the differences between equivalence, row equivalence and similarity in matrices?

asked Feb 18, 2018 at 16:10

2 votes

2 answers

2k views

What is the expected number of children until having at least a girl and a boy?

asked Apr 1, 2018 at 18:29

2 votes

2 answers

185 views

$\sum_1^\infty a_n$ converges iff $\sum_0^\infty 2^ka_{2^k}$ converges (Rudin)

asked Jan 21, 2018 at 20:28

2 votes

1 answer

980 views

$\lim \sup$ and $\lim \inf$ of root and ratio test sequences of a series (Rudin)

asked Jan 24, 2018 at 19:24

1 vote

1 answer

96 views

$\sum a_nb_n$ convergence theorem (Rudin)

asked Jan 25, 2018 at 16:36

1 vote

1 answer

470 views

Every nonempty perfect set in $\mathbb R^k$ is uncountable: Rudin's argument

asked Jan 14, 2018 at 12:45

1 vote

1 answer

197 views

The subsequential limits of a sequence {$p_n$} in a metric space $X$ form a closed subset of $X$ (Rudin)

asked Jan 17, 2018 at 10:11

1 vote

1 answer

122 views

Implicit differentiation for $x^2+y^2-x^2y^2=1$ while the slope of the curve must be ($0$)

asked Aug 11, 2017 at 4:05

1 vote

2 answers

362 views

Showing the local maximum or minimum, while the function changes sign infinitely often

asked Sep 4, 2017 at 12:51

1 vote

1 answer

166 views

Proving: $\lim _{x \rightarrow \infty} \ f(x)=\lim_{t \rightarrow 0^+} \ f(1/t)$ [duplicate]

asked Sep 7, 2017 at 12:32

1 vote

1 answer

304 views

GRE probability question: What is the probability that it is a woman, or a man who is not bringing a dessert?

asked Oct 21, 2017 at 18:03

1 vote

1 answer

443 views

how to find the number of combinations that has at least 2 numbers alike in the experiment of 4 people each rolling a fair die

asked Oct 25, 2017 at 23:30

1 vote

1 answer

464 views

What's the expected number of locations with exactly one phone number in a hash table?

asked Apr 4, 2018 at 16:35

1 vote

2 answers

1k views

Expected number of different colors of balls obtained before getting the first red ball

asked Apr 5, 2018 at 12:40

1 vote

1 answer

26 views

A question on the derivation of the PDF of the general normal distribution

asked Apr 24, 2018 at 20:31

1 vote

0 answers

122 views

The derivation of the Binet-Cauchy Formula of Determinants from matrix multiplication

asked Feb 19, 2018 at 5:30

1 vote

1 answer

522 views

Every rearrangement of an absolutely convergent series converges to the same sum (Rudin)

asked Jan 28, 2018 at 19:11

1 vote

2 answers

988 views

proof of continuity of coordinate functions (Rudin)

asked Jan 31, 2018 at 18:40

1 vote

0 answers

85 views

Why is the ring of matrices of order $n$ is an algebra - Gantmacher?

asked Nov 15, 2017 at 1:35

1 vote

1 answer

316 views

If $E$ is an infinite subset of a compact set $K$, and $E$ has a limit point in $K$; where is the finite subcover?

asked Jan 11, 2018 at 18:13

1 vote

1 answer

47 views

Understanding the definition of a limit using neighborhoods in $R^1$ (Rudin)

asked Feb 6, 2018 at 20:31

1 vote

1 answer

234 views

Continuity Arguments and Limits on Matrices - Resources

asked Feb 7, 2018 at 20:15

1 vote

0 answers

32 views

The proof of "Two rectangular matrices of the same dimension are equivalent $\iff$ they have the same rank"

asked Feb 18, 2018 at 13:03

0 votes

1 answer

43 views

Continuity and Compactness, Is this mapping onto? (Rudin) [duplicate]

asked Feb 3, 2018 at 20:45

0 votes

0 answers

29 views

Is this a good imagination of $f$ (4.1 Remark; Rduin)

asked Feb 6, 2018 at 15:00

0 votes

1 answer

169 views

The characteristic values of the p-th compound matrix

asked Feb 24, 2018 at 18:17

0 votes

0 answers

48 views

why is $P(Y=k|X=15, B)=P(Y=k|B)$ in the following argument?

asked Mar 26, 2018 at 13:25

0 votes

1 answer

109 views

If $X, Y, Z$ are positive i.i.d. r.v.s, why is $E(\frac X{X+Y+Z})=E(\frac Y{X+Y+Z})=E(\frac Z{X+Y+Z})$?

asked Apr 29, 2018 at 16:17

0 votes

1 answer

349 views

A conceptual definition of a Matrix Determinant

asked Nov 13, 2017 at 3:03

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34 Questions

Every infinite subset of $E$ in $\mathbb R^k$ having a limit point in $E$ implies $E$ is closed

What are the differences between equivalence, row equivalence and similarity in matrices?

What is the expected number of children until having at least a girl and a boy?

$\sum_1^\infty a_n$ converges iff $\sum_0^\infty 2^ka_{2^k}$ converges (Rudin)

$\lim \sup$ and $\lim \inf$ of root and ratio test sequences of a series (Rudin)

$\sum a_nb_n$ convergence theorem (Rudin)

Every nonempty perfect set in $\mathbb R^k$ is uncountable: Rudin's argument

The subsequential limits of a sequence {$p_n$} in a metric space $X$ form a closed subset of $X$ (Rudin)

Implicit differentiation for $x^2+y^2-x^2y^2=1$ while the slope of the curve must be ($0$)

Showing the local maximum or minimum, while the function changes sign infinitely often

Proving: $\lim _{x \rightarrow \infty} \ f(x)=\lim_{t \rightarrow 0^+} \ f(1/t)$ [duplicate]

GRE probability question: What is the probability that it is a woman, or a man who is not bringing a dessert?

how to find the number of combinations that has at least 2 numbers alike in the experiment of 4 people each rolling a fair die

What's the expected number of locations with exactly one phone number in a hash table?

Expected number of different colors of balls obtained before getting the first red ball

A question on the derivation of the PDF of the general normal distribution

The derivation of the Binet-Cauchy Formula of Determinants from matrix multiplication

Every rearrangement of an absolutely convergent series converges to the same sum (Rudin)

proof of continuity of coordinate functions (Rudin)

Why is the ring of matrices of order $n$ is an algebra - Gantmacher?

If $E$ is an infinite subset of a compact set $K$, and $E$ has a limit point in $K$; where is the finite subcover?

Understanding the definition of a limit using neighborhoods in $R^1$ (Rudin)

Continuity Arguments and Limits on Matrices - Resources

The proof of "Two rectangular matrices of the same dimension are equivalent $\iff$ they have the same rank"

Continuity and Compactness, Is this mapping onto? (Rudin) [duplicate]

Is this a good imagination of $f$ (4.1 Remark; Rduin)

The characteristic values of the p-th compound matrix

why is $P(Y=k|X=15, B)=P(Y=k|B)$ in the following argument?

If $X, Y, Z$ are positive i.i.d. r.v.s, why is $E(\frac X{X+Y+Z})=E(\frac Y{X+Y+Z})=E(\frac Z{X+Y+Z})$?

A conceptual definition of a Matrix Determinant