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William Hilbert
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  • Member for 8 years, 5 months
  • Last seen more than 8 years ago
16 votes

How big is infinity?

7 votes

What was the book that opened your mind to the beauty of mathematics?

5 votes
Accepted

Ramanujan's personification of small positive integers

3 votes

For all reals $x$, prove $2^x > x$

2 votes

Show that if $(m,n) = 1$, then for any number $p$, we have $(p,mn) = (p,m)(p,n)$.

1 vote

Frog Jump Problem

1 vote

Prove that the straight line joining the middle point of the hypotenuse of a right angled triangle to the right angle is equal to half the hypotenuse.

1 vote

Can't find an identity for proving that $ \sum_{k=0}^{i+1} \binom {i+1} k=2^{i+1}$

1 vote
Accepted

Prove at least two points in a rectangle are within $\sqrt{5}$ of each other

1 vote
Accepted

Two circle intersection

0 votes

Prove the inequality for n>2.

0 votes

Prove that the well ordering principle is equivalent with PMI.

0 votes

Within If and Only If Proofs, why can the proof for one direction be easier than the other?

0 votes

Induction Proof that $x^n-y^n=(x-y)(x^{n-1}+x^{n-2}y+\ldots+xy^{n-2}+y^{n-1})$

0 votes

What are the properties of a prime number?

0 votes
Accepted

Evaluate $S=\Sigma\Sigma\Sigma x_ix_jx_k$