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yiyi
  • Member for 12 years, 4 months
  • Last seen more than 4 years ago
124 votes
10 answers
44k views

How can I find the surface area of a normal chicken egg?

30 votes
2 answers
2k views

a problem from 1977 all Soviet Union Mathematical Olympiad

18 votes
4 answers
165k views

How to figure out the log of a number without a calculator?

16 votes
2 answers
5k views

Is the game 2048 always solveable?

15 votes
6 answers
18k views

Difference in terminology between Let and Assume?

14 votes
1 answer
1k views

Does every closed curve contain the vertices of a square?

12 votes
3 answers
28k views

Question regarding usage of absolute value within natural log in solution of differential equation

12 votes
7 answers
3k views

How to say $(a,b]$ and $[a,b)$ in English?

11 votes
3 answers
952 views

Why would some elementary number theory notes exclude 0|0?

11 votes
3 answers
6k views

The most common theorems taught in Abstract Algebra

11 votes
1 answer
1k views

Confused about an integral from MIT integration bee 2012

9 votes
1 answer
6k views

half-derivative of $x^2$

8 votes
2 answers
255 views

Wrong solution for $\int \frac{1 - e^x}{e^x}\, dx$

8 votes
1 answer
4k views

What do these arrows mean? (Froda's Thm)

8 votes
2 answers
216 views

$\sum \limits_{k=1}^{\infty} \frac{6^k}{\left(3^{k+1}-2^{k+1}\right)\left(3^k-2^k\right)} $ as a rational number.

7 votes
1 answer
1k views

Construct with a rule and compass a square, given one point from each side

7 votes
1 answer
125 views

$\int 5\sqrt{x^3+2x}\, \textrm{d}x$

7 votes
2 answers
187 views

Help make Wonder Woman's box big.

7 votes
2 answers
2k views

Question about an article by Nassim Nicholas Taleb about the problems with standard deviation.

6 votes
1 answer
598 views

Derivative of $\sec^{-1} e^{2x}$, my answer differs from wolfram alpha.

6 votes
4 answers
835 views

I am almost certain the book is wrong on this "proof" of a limit.

6 votes
5 answers
3k views

Would the answer of the square root of a square root be positive or negative?

6 votes
1 answer
968 views

Whats the mathematics behind this type of taking the rope out puzzle.

6 votes
3 answers
113k views

Find the volume of the largest right circular cone that can be inscribed in a sphere of radius r?

6 votes
1 answer
338 views

is there a cardinality between the rational and the irrationals?

6 votes
2 answers
270 views

Find the derivative in term of $x$ and $y$.

5 votes
8 answers
2k views

How to prove that $\lim\limits_{n\to\infty} \frac{n!}{n^2}$ diverges to infinity?

5 votes
2 answers
716 views

What is the probablity that a Rubik's cube is solvable if you randomly switch two squares?

5 votes
1 answer
274 views

Simplifying $(4m^3n)^\frac{1}{4} \times (8mn^3)^\frac{1}{2}$

5 votes
4 answers
355 views

solving for a coefficent term of factored polynomial.

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