User MathAdam

28 votes

2 answers

814 views

Is this a valid proof that the harmonic series diverges?

asked Mar 20, 2020 at 14:44

10 votes

4 answers

2k views

Can a function have a derivative where it has no value?

calculus real-analysis

asked Apr 22, 2018 at 6:12

8 votes

4 answers

3k views

Is there a relationship between vector spaces and fields/rings/groups?

linear-algebra group-theory ring-theory vector-spaces field-theory

asked Sep 7, 2015 at 17:47

8 votes

3 answers

1k views

Does $\lim_{x\to 0^+} \sqrt{x}$ exist or not?

limits radicals

asked Sep 10, 2015 at 12:14

7 votes

2 answers

261 views

Is this a sound demonstration of Euler's identity?

proof-verification complex-numbers polar-coordinates

asked Sep 5, 2015 at 15:54

6 votes

1 answer

158 views

How do I translate $ [(P \Rightarrow Q) \land (Q \Rightarrow T)] \Rightarrow T$ into English?

propositional-calculus

asked Jun 11, 2017 at 23:56

5 votes

2 answers

156 views

Please help me to remove Feynman's $\log_{10}$ from my eye.

logarithms

asked Dec 1, 2017 at 1:50

5 votes

0 answers

625 views

Does the arithmetic derivative have a geometric interpretation

elementary-number-theory prime-numbers

asked Dec 22, 2018 at 18:44

5 votes

3 answers

21k views

If a function is undefined at a point, is it also discontinuous at that point?

real-analysis functions continuity

asked Sep 12, 2015 at 6:01

4 votes

2 answers

127 views

How do I demonstrate the geometric meaning of a $2\times2$ matrix?

linear-algebra

asked Sep 7, 2015 at 0:53

4 votes

1 answer

3k views

Why does Desmos give a different exponential regression than my TI 84 and my Calculus text?

calculator regression-analysis

asked Jan 28, 2017 at 22:52

4 votes

2 answers

659 views

Can we solve this without cubic formula?

algebra-precalculus cubics

asked Jan 11, 2018 at 3:16

4 votes

1 answer

118 views

Does this infinite nested radical show that $\pi$ is irrational?

notation pi nested-radicals

asked Apr 22, 2020 at 17:59

3 votes

4 answers

175 views

Is this approach to the limit solution kosher?$ \lim_{n\rightarrow\infty}\frac{(n!)^{\tfrac{1}{n}}}{n}=\frac{1}{e}$

limits solution-verification limits-without-lhopital

asked Nov 6, 2020 at 21:02

3 votes

0 answers

53 views

How to write a complete solution to $i=\cos x$?

complex-numbers solution-verification

asked Oct 14, 2021 at 18:34

3 votes

1 answer

51 views

Is $\sqrt{2+\sqrt{5}}$ included in the extension field $\mathbb{Q}(\sqrt5)$?

extension-field

asked Mar 12 at 3:50

3 votes

4 answers

619 views

Does a Dedekind cut define a real number into existence?

real-numbers

asked Apr 23, 2017 at 2:28

3 votes

1 answer

74 views

How does $y=\frac{2x+2}{x+2}$ contribute to demonstrating the Dedekind cut for $\sqrt{2}$?

real-numbers

asked May 1, 2017 at 13:38

3 votes

3 answers

163 views

A right triangle has leg $n$, hypotenuse $2n+6$, and perimeter $60$. Find the lengths of all sides.

quadratics

asked Jun 2, 2017 at 5:47

3 votes

7 answers

1k views

Is the $\epsilon-\delta$ definition of a limit useful for either calculating or proving limits?

limits epsilon-delta limits-without-lhopital

asked Sep 12, 2015 at 23:25

2 votes

3 answers

124 views

Is there a general solution to $a^x + b^x =c^x$ for $x\in\mathbb{R}$?

functions puzzle

asked May 4, 2017 at 23:36

2 votes

3 answers

108 views

Is $\emptyset$ a set element?

elementary-set-theory

asked Apr 23, 2017 at 22:56

2 votes

5 answers

51 views

Is there anything in the proof for $\frac{a}{1-r}$ to show that it won't work for $|r|\gt1$ when summing an infinite geometric series?

sequences-and-series convergence-divergence geometric-series

asked Feb 24, 2018 at 23:26

2 votes

3 answers

123 views

Is there a function that maps each element of $\mathbb{Q}$ between 0 and 1 to $\mathbb{N}$?

combinatorics elementary-number-theory rational-numbers

asked Mar 26, 2021 at 19:04

2 votes

2 answers

83 views

Does the $0$ solution for $\sqrt{x\sqrt{x\sqrt{x\sqrt{x\sqrt{x...}}}}}$ hold any meaning?

nested-radicals

asked Mar 30, 2021 at 14:30

1 vote

2 answers

142 views

Fibonacci general term: How do I mend this broken derivation?

power-series generating-functions fibonacci-numbers negative-binomial

asked Sep 7, 2020 at 2:20

1 vote

2 answers

337 views

What is the significance of the number $0.739085133$ (the solution of $x = \cos(x)$)?

trigonometry

asked Apr 26, 2018 at 2:10

1 vote

0 answers

59 views

Is there any way to rescue this trig identity proof?

trigonometry

asked Dec 19, 2018 at 12:35

1 vote

2 answers

65 views

What (if any) system of equations would solve this problem?

algebra-precalculus

asked Dec 20, 2018 at 7:33

1 vote

1 answer

56 views

How to solve this vector problem involving more than one unknown?

algebra-precalculus trigonometry euclidean-geometry physics

asked Jan 20, 2019 at 6:39

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47 Questions

Is this a valid proof that the harmonic series diverges?

Can a function have a derivative where it has no value?

Is there a relationship between vector spaces and fields/rings/groups?

Does $\lim_{x\to 0^+} \sqrt{x}$ exist or not?

Is this a sound demonstration of Euler's identity?

How do I translate $ [(P \Rightarrow Q) \land (Q \Rightarrow T)] \Rightarrow T$ into English?

Please help me to remove Feynman's $\log_{10}$ from my eye.

Does the arithmetic derivative have a geometric interpretation

If a function is undefined at a point, is it also discontinuous at that point?

How do I demonstrate the geometric meaning of a $2\times2$ matrix?

Why does Desmos give a different exponential regression than my TI 84 and my Calculus text?

Can we solve this without cubic formula?

Does this infinite nested radical show that $\pi$ is irrational?

Is this approach to the limit solution kosher?$ \lim_{n\rightarrow\infty}\frac{(n!)^{\tfrac{1}{n}}}{n}=\frac{1}{e}$

How to write a complete solution to $i=\cos x$?

Is $\sqrt{2+\sqrt{5}}$ included in the extension field $\mathbb{Q}(\sqrt5)$?

Does a Dedekind cut define a real number into existence?

How does $y=\frac{2x+2}{x+2}$ contribute to demonstrating the Dedekind cut for $\sqrt{2}$?

A right triangle has leg $n$, hypotenuse $2n+6$, and perimeter $60$. Find the lengths of all sides.

Is the $\epsilon-\delta$ definition of a limit useful for either calculating or proving limits?

Is there a general solution to $a^x + b^x =c^x$ for $x\in\mathbb{R}$?

Is $\emptyset$ a set element?

Is there anything in the proof for $\frac{a}{1-r}$ to show that it won't work for $|r|\gt1$ when summing an infinite geometric series?

Is there a function that maps each element of $\mathbb{Q}$ between 0 and 1 to $\mathbb{N}$?

Does the $0$ solution for $\sqrt{x\sqrt{x\sqrt{x\sqrt{x\sqrt{x...}}}}}$ hold any meaning?

Fibonacci general term: How do I mend this broken derivation?

What is the significance of the number $0.739085133$ (the solution of $x = \cos(x)$)?

Is there any way to rescue this trig identity proof?

What (if any) system of equations would solve this problem?

How to solve this vector problem involving more than one unknown?