30,751 reputation
33196
bio website brilliant.org
location San Francisco, CA
age 30
visits member for 1 year, 11 months
seen 6 mins ago

Calvin Lin is the Math Challenge Master at Brilliant. He was born in Singapore, represented his home country at the International Mathematical Olympiad in 2001 and 2002, and trained the Singapore IMO team in 2005. Calvin studied economics and mathematics at the University of Chicago and graduated with a joint BA-MA in Mathematics in four years. While he was a student at the U of C, he continued training bright young mathematicians as an instructor for the Young Scholars Program for four years.


4h
comment How many ways to make a connected graph using 4, 5, 6 edges?
If it has 4 edges, it must be a tree, and that is well studied.
16h
comment Find Minimum value of $P=\frac{1}{1+2x}+\frac{1}{1+2y}+\frac{3-2xy}{5-x^2-y^2}$
@MusséRedi There are other points, like $\approx (1.1, 1.2) $. See Wolfram.
2d
comment More rigorous method for this elementary problem?
Note: That is not the only solution.
2d
comment $2x^2+ 3y^2+4z^2 =1$ find the maximum of $4x+3y+2z$
Hint: Cauchy Schwarz
2d
awarded  Caucus
Dec
9
comment How prove this polynomials $p_{j}(x)$ and $p_{k}(x)$ are relatively prime (2014,Putnam problem)
Putnam solutions, compiled by Kiran Kedlaya
Dec
9
comment Determining information in minimum trials (combinatorics problem)
Can you explain the formal presentation? It seems to be that you think that the answer guesses must be fixed $v_i$, whereas I think that the original question allows the student to choose how to answer after each mock test.
Dec
7
reviewed Looks OK Proving the symmetry of the Ricci tensor?
Dec
7
reviewed Leave Open Modification of the Ramsey number
Dec
7
reviewed Leave Open Prove that some local noetherian integral domain is a field
Dec
7
reviewed Close Proving that if a set $A$ is infinite then necessarily $|A|\geq|\mathbb{N}|$
Dec
7
reviewed Leave Open How to calculate the probability of busting in Black Jack?
Dec
7
reviewed Leave Open Finding the values of $a$ and $b$.
Dec
7
reviewed Leave Closed Phase retrieval via SDP (semidefinite program) of 2D test image (Matrix completion)
Dec
7
reviewed No Action Needed Assistance with Bayesian Random Effects and Mixed Effects Models
Dec
7
reviewed No Action Needed “Integer average” of two integer numbers
Dec
7
comment Let $a, b, c$ be positive real numbers such that $a + 2b + 3c = 26$ and $a^2 + b^2 + c^2 = 52$.
My solution answered his question. I'm wondering why the other solutions (posted after mine) are ignoring the actual question. Thanks.
Dec
7
comment Let $a, b, c$ be positive real numbers such that $a + 2b + 3c = 26$ and $a^2 + b^2 + c^2 = 52$.
Note that OP is asking "What am I doing wrong", as opposed to "How do I solve this problem".
Dec
7
comment Let $a, b, c$ be positive real numbers such that $a + 2b + 3c = 26$ and $a^2 + b^2 + c^2 = 52$.
Note that OP is asking "What am I doing wrong", as opposed to "How do I solve this problem".
Dec
6
answered Let $a, b, c$ be positive real numbers such that $a + 2b + 3c = 26$ and $a^2 + b^2 + c^2 = 52$.