366 INDEX
tournament, 95, 102
transformation, 123, 124
transformations, 257, 296-3 14
and Felix Klein, 257, 298
and Henri Poincare, 257
composition, 298, 302, 304, 313
homothety, 305-307
and concurrence, 306
inversion, 307-3 11
algorithm for, 307, 313
rigid motions, 298-305
glide reflection, 301
reflection, 301
rotations, 302-305
translations, 298
shearing, 27 1
transversal,260
trapezoid, 279
triangle inequality, 51, 260
triangle( s)
circumcenter, 266
exterior angle measure, 261
incenter, 266
inscribed in circle, 266
isosceles, 262
medial, 269
orthocenter, 267
sum of interior angles, 26 1
triangles
congruent, 259
similar, see similar triangles
triangulation, 48, 55, 217
trigonometry, 280
TS, 40
twin prime, 234
Two Men of Tibet problem, 116-1 18
UCLA, 339
USAMO, see American mathematical
contests
Vadala, Derek, 20
Vandermonde convolution formula, 206
vectors, 298- 301
and complex numbers, 121, 122, 128
and lattice points, 53
and triangle inequality, 51
as motions, 298
basis, 34
dot product, 301
vertex of graph, see graph theory
vertical angles, 260
Vietnam, 8
Visual Complex Analysis, 120
W^5 ,40
weights, method of, 294
well-ordering principle, 74, 102
Wilf, Herbert, 138
Wilson's theorem, 68, 252
WLOG, 41
yoga, 23
Zen in the Art of Archery, 23
zeta function, 162, 163, 349, 354