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Pubbie
  • Member for 10 years, 8 months
  • Last seen more than 8 years ago
  • Indiana
9 votes
2 answers
8k views

Proving that a ring is not a Principal Ideal Domain

8 votes
2 answers
2k views

Struggling with Topology. Any advice?

4 votes
2 answers
696 views

What's after undergrad? Advice needed.

3 votes
3 answers
1k views

Are curves closed in $\mathbb{R}\times \mathbb{R}$ with the standard topology?

3 votes
3 answers
3k views

Show that the function is not continuous anywhere

3 votes
2 answers
2k views

Is the set of all functions $f:Z_+\rightarrow Z_+$ that are eventually constant countable.

3 votes
3 answers
2k views

Prove that $\int_a^b x^2 dx = \frac{b^3-a^3}{3}$

2 votes
5 answers
182 views

$\lim_{x\rightarrow\infty}(\frac{x+1}{x-1})^{\sqrt{x^2-1}}$

2 votes
1 answer
104 views

Algebraic Extension help!

2 votes
1 answer
6k views

The boundary of the union of two sets is a subset of the union of boundaries

1 vote
1 answer
969 views

Delta Epsilon Quotient Proof

1 vote
1 answer
125 views

Mathematica Question regarding NSolve

1 vote
1 answer
82 views

Continuity Property Proof Check

1 vote
2 answers
59 views

Show $f(rx) = [f(x)]^r$ where $r\in\mathbb{Q}$.

1 vote
3 answers
141 views

If $f$ is continuous, $f(1) >1$ and $f(x+y)=f(x)f(y)$, then $f$ is increasing.

1 vote
5 answers
949 views

If $f'(0)$ exists then show that $f$ is differentiable everywhere.

1 vote
1 answer
606 views

Help with set theory proof

1 vote
1 answer
40 views

Diff. Eq. Example with Matrices

1 vote
1 answer
86 views

Functions of Matrices History

1 vote
1 answer
839 views

Square Root of a Diagonalizable Matrix

1 vote
2 answers
433 views

Prove: $f(x)=e^{ax}$ is continuous on $\mathbb{R}$

0 votes
2 answers
737 views

If $f$ is continuous at $x_0$ and $f(x_0)>M$, then $f(x)>M$ in some neighborhood of $x_0$

0 votes
2 answers
3k views

Using induction to prove a formula for $\sin x+\sin 3x+\dots+\sin (2n-1)x$

0 votes
1 answer
89 views

Proving a function is bijective.

0 votes
1 answer
2k views

Limit inferior and limit superior proof