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Javier's user avatar
Javier's user avatar
Javier
  • Member for 13 years, 7 months
  • Last seen this week
  • Buenos Aires, Argentina
65 votes
4 answers
574k views

How to tell if a set of vectors spans a space?

46 votes
6 answers
31k views

If a function has a finite limit at infinity, does that imply its derivative goes to zero?

34 votes
1 answer
10k views

Is there any meaning to an "infinite derivative"?

27 votes
5 answers
14k views

Difference between $\implies$ and $\;\therefore\;\;$?

25 votes
8 answers
25k views

Proving that $\lim\limits_{x \to 0}\frac{e^x-1}{x} = 1$

25 votes
5 answers
5k views

Why do we think of a vector as being the same as a differential operator?

16 votes
3 answers
3k views

Intuitive understanding of integral of vector valued functions

12 votes
6 answers
4k views

Solving $\lim\limits_{x \to 0^+} \frac{\ln[\cos(x)]}{x}$

11 votes
2 answers
2k views

Motivation for definition of logarithm in Feynman's Lectures on Physics

10 votes
3 answers
841 views

Does $a^n \mid b^n$ imply $a\mid b$?

8 votes
2 answers
622 views

Solving $y'' + (ax+b)y = 0$

8 votes
2 answers
571 views

How do we know that $\exp(x)$ agrees with raising a number to a rational power?

8 votes
4 answers
364 views

Help solving a limit

7 votes
2 answers
749 views

How to justify this differential manipulation while integrating?

6 votes
2 answers
13k views

Subgroup criterion.

6 votes
1 answer
553 views

What kind of object is the push forward of a vector field?

6 votes
1 answer
237 views

If $B$ is an ideal of $A$ then $B[x]$ is an ideal of $A[x]$ - what's wrong with my proof?

6 votes
1 answer
366 views

Tips on this olympiad problem

5 votes
2 answers
987 views

How can the graph of a complex function be embedded in three dimensional space?

5 votes
4 answers
272 views

Taking the derivative of $\frac1{x} - \frac1{e^x-1}$ using the definition

4 votes
2 answers
957 views

Maclaurin series of $\frac{1}{1+x^2}$

4 votes
2 answers
579 views

Why does this method for solving matrix equations work?

4 votes
1 answer
8k views

Prove that the set of positive real numbers is not bounded from above

4 votes
2 answers
5k views

Can I apply Rolle's theorem in reverse?

4 votes
3 answers
6k views

How to prove $\lim_{(x,y)\to(0,0)} \frac{xy}{x+y} = 0$

4 votes
2 answers
206 views

Calculating $\int_0^\infty(\log t)^n e^{-t}\ dt$

4 votes
2 answers
342 views

Why do we get two solutions when inverting $y = \sinh x$?

4 votes
1 answer
152 views

Confused on definition of strong induction

4 votes
1 answer
324 views

Confusion regarding change of variables in ODEs

4 votes
2 answers
384 views

Does the matrix exponential take open sets into open sets?