Smuttynose Island wrote:IMSANITY Round 1 TU 3 wrote wrote:The \"wisted" this is a 3-dimensional parametric curve. Casus irreducibilis refers
to the situation when the roots of a polynomial of this type are all real but
require the use of complex numbers to solve for. Their roots can be found
with * Cardano's formula, but the fact that the roots tend to not be constructible renders
unsolvable two of the three problems of ancient Greek geometry, including trisecting an
angle. Polynomials of this type have exactly one in
ection point and have no maximum or
minimum. FTP, give this adjective describing things with degree 3.
ANSWER: cubic (prompt on \degree 3" before the giveaway)
You claim that there is no difficulty cliff in this TU, but whenever you go from a topic that is taught in an AP Class to a clue that is a simple as "name this adjective that describes things with degree 3" you have a difficulty cliff. If you don't understand why this is the case it is similar to writing a TU on Louis XIV and going from "This man recognized the King of England by signing the Treaty of Ryswick at the end of the War of the Grand Alliance." to "For 10 points, name this "sun king" of France, the fourteenth of a certain name." Additionally, this TU does in fact contain a non-uniquely identifying clue as many high-order polynomials contain one inflection point and no maximum or minimum (example: f(x)=x^5)
Also would it be possible for a moderator to break off the math discussion from this thread into a seperate thread?
Leucippe and Clitophon wrote:Andrew is confusing local extrema for global extrema, or perhaps the question is not clear enough.
whitesoxfan wrote:So far, you've failed to demonstrate that IMSANITY 1 Math contained anything other than early clues that sometimes started out too difficult, because only a handful of high schoolers would know those clues. The answer lines were for the most part accessible (a term which means convertable, not the other aspects of a good question that Daniel has tried to infuse into it). I have yet to see a single example of a large difficulty cliff, yet you claim that most of the tossups contained one. The one complaint I haven't seen people making about the math is that clues were misordered, yet you also say that "plenty" contained them. Finally, correctness and uniquely identifying the answer are the two most important aspects of questions, and saying that a difficult lead-in is worse than a blatantly incorrect clue is just wrong. IMSANITY 1 Math was not by any stretch of the imagination bad.
Round 1 wrote:The \twisted" this is a 3-dimensional parametric curve. Casus irreducibilis refers
to the situation when the roots of a polynomial of this type are all real but
require the use of complex numbers to solve for. Their roots can be found
with * Cardano's formula, but the fact that the roots tend to not be constructible renders
unsolvable two of the three problems of ancient Greek geometry, including trisecting an
angle. Polynomials of this type have exactly one inflection point and have no maximum or
minimum. FTP, give this adjective describing things with degree 3.
Round 1 wrote:This is the smallest number of people needed to guarantee at least a 50 percent
chance that some two will share the same birthday. At the 1900 International
Congress of Mathematicians, David Hilbert set forth this many problems as a
challenge to twentieth century mathematics and Book I of The Elements begins
with this many basic denitions, including \point" and \line". Excluding the
* initial arrangement, there are this many ways to reorder four books on a shelf. Itself a
Germain prime, FTP, name this number which proves that 11 is a Germain prime on account
of it exceeding the double of 11 by 1.
Round 2 wrote:The sigma variety of this is the set of measurable events in a probability space.
Ideals and modules are the subject of the commutative type, and vector spaces
are the focus of the linear type. Deriving its name from a 9th century book by
* al-Khwarizmi about \balancing" and \restoration", this word comes from the Arabic for
\the method". Groups, rings, and elds are studied in its abstract type, but in general it is
concerned with the existence and determination of solutions of equations. FTP, name this
branch of mathematics, the bane of many high school freshmen.
Round 2 wrote:Some methods of attacking this problem involve looking for the largest interior
angle or considering the convex hull. Dynamic programming techniques can solve
this problem exactly in exponential time, but the Nearest Neighbor heuristic
can nd an approximate solution to this problem much faster. Cutting-plane
methods to developed by Dantzig, Fulkerson, and Johnson to solve this on *
United State capitals. By a reduction of the Hamiltonian Cycle Problem, Richard Karp
showed that this problem is NP-complete. Finding the cheapest of n factorial possible paths
is, FTP, this problem which seeks the shortest possible route through n cities.
Round 3 wrote:Riemann's namesake type of this gure is another term for the extended complex
plane, and Kepler's Conjecture concerns the most ecient way to pack these. For
triangles embedded on this surface, the properties of similarity and congruence
coincide, since area is proportional to the angular excess. This gure * maximizes
volume for a given surface area, the latter of which is four times the area of one of its great
circles. The collection of points in 3-dimensional-space equidistant from the center is, FTP,
this higher-dimensional analog of a circle.
Round 3 wrote:In 2004, Marcus and Tardos proved a conjecture of Stanley and Wilf on the
number of these avoiding a certain pattern. These can be classied as even or
odd depending on the number of transpositions needed to express them. One
is called a derangement if no object occupies its original position. A random
one can be generated with the Knuth * shue. There are six of these for the letters
ABC, 120 for the numbers one through ve, and 5040 for seven people standing in line.
A reordering of a set of objects is, FTP, this mathematical structure, often paired with
combinations.
Round 3 wrote:The Chebyshev Inequality guarantees that the probability that a random variable
di
ers from its mean by more than alpha is at most this quantity divided by alpha
squared. This quantity preserves addition when applied to independent random
variables. For the outcome of a fair die, this quantity is thirty-ve twelfths, or
about 2:92. Dened as the * expectation of the square of the quantity of a random
variable minus its mean, this parameter is usually calculated as the mean of the square
minus the square of the mean. Usually denoted by sigma squared, FTP, name this measure
of the spread of a probability distribution.
Round 4 wrote:All solutions to a logistic di
erential equation have either one or two of these.
Their name was coined by Appolonius to mean \not meeting", although modern
interpretation allows them to * intersect their corresponding curves. For rational
functions, the quotient resulting from long division yields the horizontal and oblique types
and the zeroes of the denominator help determine the rest. The graph of arctangent of x
has two of these, but the graph of tangent of x has innitely many vertical ones separated
by distances of pi. The limiting behavior of functions near positive or negative innity are,
FTP, these lines that graphs approach.
Round 4 wrote:In algebra, a field must have at least this many elements. This is the sum of the
reciprocals of the triangular numbers as well as the minimum possible sum of a
positive number and its reciprocal. The * Goldbach Conjecture asserts that this is
the largest even number not expressible as a sum of two primes. The number of subsets of
a set of size n is this number to the nth power. The base of binary arithmetic is, FTP, this
smallest prime number.
Round 4 wrote:Roth's Theorem guarantees the existence of these groups of numbers in any
dense subset of the natural numbers, and the Green-Tao Theorem guarantees
arbitrarily long ones in the primes. Dirichlet showed that these groups always
contain prime numbers if the rst two terms are coprime. A young * Gauss
developed a method for summing the elements of one of these, which was to average the rst
and last terms and multiply by the number of terms. Discrete linear growth characterizes,
FTP, this group of numbers formed by iteratively adding a common di
erence to an initial
term.
Round 5 wrote:Leonhard Euler left his native Switzerland for this country to join its academy of
sciences. One mathematician from this country rst proved Bertrand's Postulate
that there is always a prime number between any positive integer n and 2n, and
another, along with Janos Bolyai, developed non-Euclidean geometry. In 2006,
the Fields Medal was rejected by the mathematician from this country who
proved the Poincare Conjecture.* Chebyshev, Lobachevsky, and Perelman hailed from,
FTP, this country in which Euler was a member of the St. Petersburg Academy.
Round 5 wrote:Only 47 numbers are known to have this property, the largest of which has
nearly 26 million digits. Euler proved that the Mersenne primes are in one-to-
one correspondence with the even types of these. No * odd numbers are known to
have this property, although if any do exist, they have at least nine distinct prime factors.
Numbers with this property include 496 and 8128, although more common examples are 6
and 28. FTP, name this property of numbers whose proper divisors sum to themselves.
Round 5 wrote:This is the only one of Peano's axioms for the natural numbers that is second-
order. A transnite version of this can be used on large innite sets. This exists
in strong and weak forms, both of which are logically equivalent to the well-
ordering principle of the natural numbers. In proofs, it is used by establishing
a * base case and then demonstrating a namesake step invoking a namesake hypothesis.
Often stated as \if S of zero is true and S or n implies S of n + 1, then S of n holds for all
natural numbers n", FTP, name this principle and proof technique which progresses from
specic to general, a complement to deduction.
Round 6 wrote:The Sylvester-Gallai Theorem states that if a nite collection of points in the
plane does not have this property, then some line contains exactly two of them.
The center of the nine-point circle, orthocenter, and circumcenter of a triangle
have this property, and a set of points in the plane is said to be in general position
if no * three have this property. Two vectors have this property if they are multiples of
each other. Any three points not having this property determine a unique plane. Any two
points have, FTP, this property in which a single line can be drawn through them.
Round 6 wrote:One of these seeks a method to nd generators of rational points on elliptic
curves, and another investigates the complexity gap between computability and
veriability. Two of these have applications in physics, one in
uid mechanics
and the other in quantum eld theory. The most famous of these involves the
distribution of prime numbers. To date, only one of these seven problems. The
solution to any one of these comes with a * $1,000,000 prize from the Clay Mathematics
Institute. First introduced in May 2000, FTP, give the collective name of these problems,
including the Poincare Conjecture, P versus NP, and the Riemann Hypothesis.
Round 6 wrote:This mathematician generalized the binomial theorem to powers of multinomials.
His unpublished proof of Fermat's Little Theorem is the rst known to exist. He
made two trips to England in the 1670's, which would later become a source of
contention. Among his most well-known contributions are notational, including
the * elongated \S" and \d y over d x". These appeared in his book New Method for Maxima
and Minima, and Also for Tangents, Which is Not Obstructed by Irrational Quantities, in
which he laid out his most important discoveries. FTP, name this German mathematician
who, independently of Newton, developed calculus.
Round 7 wrote:The x-coordinate of this point can be computed as the double integral of x \d
A" divided by the area of the gure, and the y-coordinate satises the analogous
formula. Pappus's theorem says that the volume of a solid of revolution is
the area of the revolved gure times the distance traveled by this point, which
remains xed under any isometries of the gure. For a * triangle, its coordinates
are the arithmetic means of those of its vertices, and this point is the intersection of the
triangle's medians. Also called the barycenter, FTP, identify this point, the center of mass
of a gure.
Round 7 wrote:In the graphs of this type of function, a horizontal translation is equivalent to
a vertical dilation, as this type of function satises f of the quantity x plus y
close quantity equals f of x times f of y. An equiangular spiral is the result of
graphing this kind of function in the polar plane. The product of any two of
these functions is * also of this type, as is any power of one of them. Di
erentiating one
of these functions yields a multiple of that function. The inverses of logarithmic functions
are, FTP, this type, subject of a namesake growth.
Round 7 wrote:This unary operation can be dened in any quadratic extension, and in its most
common form, it forms the only nonidentity ring isomorphism of the complex
numbers xing the reals. As a result, for every * root of a polynomial with real
coefficients, this is also a root. Most often denoted with an overline, it is used when dividing
as it rationalizes the denominator. Found in its complex form by negating the imaginary
part, FTP, name this number given by the formula a minus b i.
Round 8 wrote:The set of numbers which can be expressed as a sum of two of these is closed
under multiplication according to a formula of Brahmagupta and Fibonacci.
These integers have an odd number of factors, and every natural number is the
sum of four of them by Lagrange's Theorem. The sum of any two consecutive *
triangular numbers is one, as is the sum of any initial segment of the positive odd integers.
When divided by four, they must leave a remainder of 0 or 1, and they cannot end with the
digits 2, 3, 7, or 8. FTP, name this group of integers, obtained by multiplying an integer by
itself.
Round 8 wrote:A theorem of Fortuin, Kasteleyn, and Ginibre states that increasing events are
positively correlated and is known as the FKG one of these. Jensen's states that
convex functions lie below their secant lines, and Markov's shows that a random
variable cannot be large with high probability. A more notable one implies states
that * x plus y is at least 2 times the square root of x y and is known as the arithmetic
mean-geometric mean one, and another states that the length of one side of a triangle is
at least the di
erence and at most the sum of the other two side lengths. Relationships
comparing two quantities are, FTP, these, exemplied by e to the x is greater than or equal
to one plus x.
Round 9 wrote:A xed point of a function is an intersection of its graph with this entity, which
is the best linear approximation to y equals sine of x around x equals zero.
Multiplying the graph of a function by the matrix with rst row 0 1 and second
row 1 0 re
ects across it, which produces the * graph of the function's inverse, and a
function composed with its inverse yields this curve. Having one intercept and making a 45
degree angle with the positive x axis, FTP, name this line with a slope of one and passing
through the origin.
Round 9 wrote:While this curve is not sinusoidal, its height is proportional to its arclength,
causing it to obey simple harmonic motion, and Christiaan Huygens used this
isochronous curve to design a more accurate pendulum clock. As shown by
Newton and Bernoulli, it is also a solution to the * brachistochrone problem, as a
frictionless object accelerated only by gravity will travel between its endpoints faster than
along any other curve. Described with the parametric equations x equals r t minus r sine t
and y equals r minus r cosine t, FTP, identify this curve swept out by a point on a circle
rolling along a line.
Round 19 wrote:Powers of this number, equal to twice the cosine of =5 radians, were used
by John Conway to show that in the game of Desert Solitaire, no armies can
advance more than ve units. Contrary to popular belief, some historians now
believe that this number, as opposed to the square root of two, to be the rst
number ever proved to be irrational. Research has discredited theories about
the * aesthetic value of this number, which can be obtained as the limit of the quotient of
consecutive Fibonacci numbers. FTP, name this number which exceeds its reciprocal by 1.
Round 10 wrote:This country is home to the Miklos Schweitzer Competition, a 10-day mathematics
contest for undergraduates, which is sponsored by the Janos Bolyai society.
With the exception of the USSR and China, this country has won the International
Mathematics Olympiad more than any other. This country's eponymous
algorithm was developed by Kuhn to solve the assignment problem. One mathematician
from this country worked with Morganstern to write * Theory of Games
and Economic Behavior. In addition to John von Neumann, this country is home to a mathematician
with a namesake distance measuring collaboration. FTP, name this European
country, the home of Paul Erd}os.
Round 11 wrote:It is widely believed that the cuneiform writing on the Plimpton 322 tablet
represents these. Babylonians had a formula to compute these, although it was
only a special case of the general formula given in Book 10 of Euclid's The
Elements. Rational points on the unit circle are in one-to-one correspondence
with these * groups of numbers. Every positive integer appears as an element in at least
one of these, but in the primitive type, in which the elements share no common factors, only
odd integers can be the largest element of the three. Including 5 12 13 and 3 4 5, FTP, name
these integer solutions to x squared plus y squared equals z squared.
Round 11 wrote:In ring theory, this number tells how many times the multiplicative identity must
be added to itself to obtain the additive identity. Euler's one of these is equal
to 2 for the plane. Setting this type of polynomial equal to 0 yields this type
of equation, and solving that equation yields the * eigenvalues of a matrix and thus
solutions to linear di
erential equations. This word can serve in place of \indicator" when
describing a function which is equal to 1 at every element of a set and 0 everywhere else.
FTP, give this word which composes, along with the mantissa, the common logarithm.
Round 12 wrote:This is the maximum value of the minimum degree of a nite planar simple
graph and the smallest number of vertices in a non-planar graph. This number
is the smallest degree of a polynomial which cannot be solved in radicals. In
geometry, this is the number of faces meeting at each vertex in the * icosahedron,
and hence, by duality, is the number of sides on each face of the dodecahedron. FTP, identify
this number, the number of Platonic solids.
Round 12 wrote:Bessel's correction is used to make this kind of variance an unbiased estimator.
This can be e
ectively done in clusters or in strata, but the convenience method
is frowned upon. Its namesake * proportion is the best point estimate of the success
probability. The e
ect of its namesake size on its namesake mean is the subject of the Law of
Large Numbers, and its namesake space consists of all possible measured events. Referring
to either a representative subgroup of a population or to data from that subgroup, FTP,
identify this term for the collecting of information for statistical analysis.
Round 12 wrote:In the 1970s, Thurston proved that each of these is either hyperbolic or is of
the torus or satellite types. The chirality of these objects can be used to study
that of certain molecules. Two of these objects are equivalent if one can be
transformed into the other through a sequence of Reidemeister moves. They
can be distinguished by their associated polynomials, such as the Alexander,
Jones, and HOMFLY, or by the * Gordian distance between them. FTP, name these
closed one-dimensional surfaces embedded in three-dimensional space, popular examples of
which are the pretzel, trefoil, and gure-eight.
nadph wrote:Perhaps I am being idiotic, but I unsure of what exactly Max's detailed critique proves, other than that IMSANITY math was of highly variable quality, and consequently its writers need more experience before their writing can be said to be good. This is also true given that we have at least two other (mostly) pyramidal sets with a significant (2/0 out of a 20/0 round) distribution of math tossups, namely the past two iterations of Scobol Solo; those math tossups certainly don't seem utterly terrible at a cursory read-through. (Someone who actually played Scobol Solo can correct me here.) Is there something (other than the lack of bonuses) that makes these sets ineligible for discussion? I haven't seen them mentioned so far.
Smuttynose Island wrote:The reason why Max's critique of IMSANITY's math TUs is pertinent is because Adam claimed that IMSANITY's math supported the opposite of my claim, namely that people knowledgeable in math would, regardless of their competency at actually writing questions or being good editors, produce, on average, better math questions.
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