# User contributions

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- 20:58, 21 April 2018 (diff | hist) . . (+16) . . USAMO Problems and Solutions
- 11:52, 21 April 2018
(diff | hist) . .
**(+768)** . . N 2018 USAMO Problems/Problem 5 (Created page with "==Problem 5== In convex cyclic quadrilateral <math>ABCD,</math> we know that lines <math>AC</math> and <math>BD</math> intersect at <math>E,</math> lines <math>AB</math> and <...") - 11:52, 21 April 2018 (diff | hist) . . (+332) . . N 2018 USAMO Problems/Problem 6 (Created page with "==Problem 6== Let <math>a_n</math> be the number of permutations <math>(x_1, x_2, \dots, x_n)</math> of the numbers <math>(1,2,\dots, n)</math> such that the <math>n</math> ra...")
- 11:51, 21 April 2018 (diff | hist) . . (+411) . . N 2018 USAMO Problems/Problem 3 (Created page with "==Problem 3== For a given integer <math>n\ge 2,</math> let <math>\{a_1,a_2,…,a_m\}</math> be the set of positive integers less than <math>n</math> that are relatively prime...") (current)
- 11:51, 21 April 2018 (diff | hist) . . (+268) . . N 2018 USAMO Problems/Problem 2 (Created page with "==Problem 2== Find all functions <math>f:(0,\infty) \rightarrow (0,\infty)</math> such that <cmath>f\left(x+\frac{1}{y}\right)+f\left(y+\frac{1}{z}\right) + f\left(z+\frac{1}...") (current)
- 11:50, 21 April 2018 (diff | hist) . . (+273) . . N 2018 USAMO Problems/Problem 1 (Created page with "==Problem 1== Let <math>a,b,c</math> be positive real numbers such that <math>a+b+c=4\sqrt[3]{abc}</math>. Prove that <cmath>2(ab+bc+ca)+4\min(a^2,b^2,c^2)\ge a^2+b^2+c^2.</cm...")
- 11:48, 21 April 2018 (diff | hist) . . (+13) . . 2018 USAMO Problems/Problem 4 (→Solution) (current)
- 11:48, 21 April 2018
(diff | hist) . .
**(+2,534)** . . N 2018 USAMO Problems/Problem 4 (Created page with "==Problem 4== Let <math>p</math> be a prime, and let <math>a_1, \dots, a_p</math> be integers. Show that there exists an integer <math>k</math> such that the numbers <cmath>a_...") - 11:45, 21 April 2018 (diff | hist) . . (-1) . . 2018 USAMO Problems (→Problem 4)
- 11:45, 21 April 2018 (diff | hist) . . (-1) . . 2018 USAMO Problems (→Problem 3)
- 11:45, 21 April 2018 (diff | hist) . . (-1) . . 2018 USAMO Problems (→Problem 2)
- 11:44, 21 April 2018 (diff | hist) . . (+34) . . 2018 USAMO Problems (→Problem 6)
- 11:44, 21 April 2018 (diff | hist) . . (+33) . . 2018 USAMO Problems (→Problem 5)
- 11:44, 21 April 2018 (diff | hist) . . (+35) . . 2018 USAMO Problems (→Problem 4)
- 11:44, 21 April 2018 (diff | hist) . . (+35) . . 2018 USAMO Problems (→Problem 3)
- 11:44, 21 April 2018 (diff | hist) . . (+35) . . 2018 USAMO Problems (→Problem 2)
- 11:43, 21 April 2018 (diff | hist) . . (+34) . . 2018 USAMO Problems (→Problem 1)
- 11:42, 21 April 2018 (diff | hist) . . (+2) . . 2018 USAMO Problems (→Problem 5)
- 11:41, 21 April 2018 (diff | hist) . . (+2) . . 2018 USAMO Problems (→Problem 6)
- 11:41, 21 April 2018 (diff | hist) . . (+1) . . 2018 USAMO Problems (→Problem 4)
- 11:41, 21 April 2018 (diff | hist) . . (+1) . . 2018 USAMO Problems (→Problem 3)
- 11:41, 21 April 2018 (diff | hist) . . (+1) . . 2018 USAMO Problems (→Problem 2)
- 11:41, 21 April 2018 (diff | hist) . . (+1) . . 2018 USAMO Problems (→Problem 1)
- 11:40, 21 April 2018 (diff | hist) . . (-285) . . 2018 USAMO Problems (→Problem 1)
- 11:40, 21 April 2018 (diff | hist) . . (-1) . . 2018 USAMO Problems (→Day 1)
- 11:40, 21 April 2018
(diff | hist) . .
**(+3,097)** . . N 2018 USAMO Problems (Created page with "==Day 1== Note: For any geometry problem whose statement begins with an asterisk (<math>*</math>), the first page of the solution must be a large, in-scale, clearly labeled di...") - 10:53, 21 April 2018 (diff | hist) . . (-243) . . 2018 USAJMO Problems/Problem 5 (→Solution)
- 02:58, 21 April 2018
(diff | hist) . .
**(+2,142)** . . 2018 USAJMO Problems/Problem 5 (→Solution) - 02:35, 21 April 2018 (diff | hist) . . (+242) . . 2018 USAJMO Problems/Problem 5 (→Solution)
- 02:03, 21 April 2018 (diff | hist) . . (+323) . . 2018 USAJMO Problems/Problem 5
- 02:01, 21 April 2018
(diff | hist) . .
**(+1,155)** . . N 2018 USAJMO Problems/Problem 6 (Created page with "==Problem 6== Karl starts with <math>n</math> cards labeled <math>1,2,3,\dots,n</math> lined up in a random order on his desk. He calls a pair <math>(a,b)</math> of these card...") - 01:57, 21 April 2018 (diff | hist) . . (+13) . . 2018 USAJMO Problems/Problem 4 (→Solution)
- 01:56, 21 April 2018
(diff | hist) . .
**(+3,912)** . . N 2018 USAJMO Problems/Problem 4 (Created page with "==Problem 4== Triangle <math>ABC</math> is inscribed in a circle of radius <math>2</math> with <math>\angle ABC \geq 90^\circ</math>, and <math>x</math> is a real number satis...") - 01:27, 21 April 2018 (diff | hist) . . (+4) . . N 2018 USAJMO Problems/Problem 5 (Created page with "TEST")
- 00:59, 15 February 2018
(diff | hist) . .
**(+849)** . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?)) - 00:34, 15 February 2018 (diff | hist) . . (+7) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:33, 15 February 2018 (diff | hist) . . (+311) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:31, 15 February 2018 (diff | hist) . . (+60) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:27, 15 February 2018 (diff | hist) . . (+148) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:26, 15 February 2018
(diff | hist) . .
**(+685)** . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?)) - 00:20, 15 February 2018 (diff | hist) . . (+7) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:18, 15 February 2018 (diff | hist) . . (+224) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:17, 15 February 2018 (diff | hist) . . (-1) . . 2018 AMC 12A Problems/Problem 23 (→Solution 2 (Overkill))
- 00:16, 15 February 2018 (diff | hist) . . (+251) . . 2018 AMC 12A Problems/Problem 23 (→Solution 3 (Nice, I Think?))
- 00:14, 15 February 2018 (diff | hist) . . (+34) . . 2018 AMC 12A Problems/Problem 23 (→Solution 2 (Overkill))
- 23:40, 5 May 2017 (diff | hist) . . (+3) . . 2017 USAJMO Problems/Problem 3 (→Solution 2)
- 23:38, 5 May 2017 (diff | hist) . . (+4) . . 2017 USAJMO Problems/Problem 3 (→Solution 2)
- 23:37, 5 May 2017 (diff | hist) . . (+149) . . 2017 USAJMO Problems/Problem 3 (→Solution 2)
- 23:36, 5 May 2017 (diff | hist) . . (+365) . . 2017 USAJMO Problems/Problem 3 (→Solution 2)
- 23:34, 5 May 2017 (diff | hist) . . (+280) . . 2017 USAJMO Problems/Problem 3 (→Solution 2)

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