Glossary of Symbols 723
CONTINUOUS FUNCTIONS
Symbol Meaning Defined on page
sgn (x) signum function 227
T(x) Thomae's function 229
lxJ greatest integer (floor) function^241
XA(x) characteristic function of (the set) A^244
! IA f restricted to the set A^246
y'X unique nonnegative nth root of x ::'.". 0 253
'P Cantor's function^270 -^273
ax ax for a > 1 and x E IR 280
xt xt for x E IR and t > 0 283
logax loga x for a, x >^0 288
'l/J1(A) oscillation of f on the set A^292
'l/J1(x) oscillation of f at x^292
F 17 -set a union of countably many closed sets 293
DIFFERENTIABLE FUNCTIONS
Symbol Meaning Defined on page
f'(xo) derivative of f at xo^297
f'_(xo), f~(xo) derivative off from the left (right) at xo^302
Dxf(x), d~~), d~f(x) alternative notation for the derivative off 306
I 9:Ji__ d
Y'dx'dxY
j(k)(x)
Tn(x)
Rn(x)
alternative notation for the derivative of f
nth derivative of f at x
nth Taylor polynomial for f
nth Taylor remainder for f
306
329
329 , 519
329,5 19