User:OneWeirdDude
I like these songs:
[edit](In no particular order:)
- Total Eclipse of the Heart, by Bonnie Tyler
- Cat's in the Cradle, by Harry Chapin
- We Didn't Start the Fire, by Billy Joel
- Secret Agent Man, by Johnny Rivers
- Born to be Wild, Steppenwolf
- Axel F, by Harold Faltermeyer
- Within Attraction, Yanni
- Stayin' Alive, BeeGees
- Oh Yeah, by Yello
- Hotel California, The Eagles
- Lemmings DDR Remix
- What is Love, by Haddaway
- Chariots of Fire, by Vangelis
- Adiemus, by Karl Jenkins (not Enya)
- California Dreamin', by The Mamas and the Papas
- Wild Child, Enya
- That "soap opera lullaby", or whatever—with no words.
- In the Hall of the Mountain King, by Edvard Grieg
- Separate Ways, by Journey
- What's Up?, by 4 Non Blondes
Mathematical Alphabet
[edit](A little hobby of mine.)
i - The imaginary unit. Also the first index/counter, and the first quaternionic unit.
j - The imaginary unit in engineering. Also the second index/counter, and the second quaternionic unit.
k - The third index/counter, and the third quaternionic unit.
m - Integer to accompany n, when necessary.
n - General integer
r - The distance from the origin in polar coordinates, the distance from the z-axis in cylindrical coordinates, and in general the unsigned distance from (x, y) = (0, 0) in other coordinate systems.
u - x-component of w, in the complex numbers; also a common substitution in calculus, and a substitute integrand in integration by parts
v - y-component of w, in the complex numbers; also a substitute integrand in integration by parts
w - The fourth dimension, and the dependent variable in coordinate hyperspace.
- (Beyond four dimensions, x with subscripts are usually used; e.g. x7 for the seventh dimension.)
- Also the dependent variable in complex numbers, with components u, v.
x - The first variable usually learned in algebra class. Also the independent variable in spatial one-dimensional functions, and one of two or more such variables in two or more dimensions. Also the signed distance from the origin on the number line, or from the y-axis on the co-ordinate plane (abscissa), or from the yz-plane in co-ordinate space, or from the yzw-realm in co-ordinate hyperspace, etc.
y - The second such variable usually learned, and the dependent variable in spatial one-dimensional functions, and one of two or more independent variables in two or more dimensions. Also the signed distance from the x-axis on the co-ordinate plane (ordinate), or from the xz-plane in co-ordinate space, or from the xzw-realm in co-ordinate hyperspace, etc.
z - The third such variable usually learned, and the dependent variable in two-dimensional functions. Also the signed distance from the xy-plane, etc. Also the independent variable in C, the complex numbers, with components x, y.
Famous past-and-present unsolved math problems
[edit]- Collatz conjecture
- Fermat's Last Theorem
- proved in 1994 by Andrew Wiles
- Four color theorem
- proved by computer in 1976 by Kenneth Appel and Wolfgang Haken
- improved in 1997 by Robertson, Sanders, Seymour, and Thomas
- further improved and simplified in 2005, by Georges Gonthier
- Goldbach's conjecture
- formulas for roots of polynomials
- cubic
- depressed form solved by Scipione del Ferro (1465-1526), and later published in 1545 by Gerolamo Cardano (1502-1576)
- general form solved by Cardano
- special cases solved by Rafael Bombelli (ca. 1526-1573) in 1572
- quartic: solved by Ludovico Ferrari (1522-1565)
- quintic and higher degrees: proven to be impossible in 1824 by Niels Abel (1802-1829)
- cubic
- odd perfect numbers
- classification of manifolds
- ongoing for three dimensions
- proved impossible in 4D by Andrey Markov Jr. in 1960
- tessellations of convex polygons
- hexagons solved by Karl Reinhardt (three cases)
- pentagons (ongoing):
- five types discovered by Reinhardt
- three more by Richard Brandon Kershner
- a ninth by Richard E. James III
- four more by Marjorie Rice (totaling 13)
- a 14th by Rolf Stein
- a 15th by Casey Mann, Jennifer McLoud-Mann, and David Von Derau