Abs (Built-in Mathematica Symbol)

Abs[z] gives the absolute value of the real or complex number z.

PrimePi (Built-in Mathematica Symbol)

PrimePi[x] gives the number of primes \[Pi] (x) less than or equal to x.

Spacer (Built-in Mathematica Symbol)

Spacer[w] displays as a spacer w printer's points wide.Spacer[{w, h}] displays as a spacer w points wide and a total of h points high.Spacer[{w, h, dh}] makes the spacer ...

Function Names as Expressions (Mathematica Tutorial)

In an expression like f[x], the 'function name' f is itself an expression, and you can treat it as you would any other expression. You can replace names of functions using ...

Sign (Built-in Mathematica Symbol)

Sign[x] gives -1, 0, or 1 depending on whether x is negative, zero, or positive.

AiryAiPrime (Built-in Mathematica Symbol)

AiryAiPrime[z] gives the derivative of the Airy function Ai^\[Prime] (z).

Operators (Mathematica Tutorial)

Some operators used in basic arithmetic and algebra. Note that the  for ∖[Cross] is distinguished by being drawn slightly smaller than the × for ∖[Times]. Interpretation of ...

BesselK (Built-in Mathematica Symbol)

BesselK[n, z] gives the modified Bessel function of the second kind K_n (z).

BesselY (Built-in Mathematica Symbol)

BesselY[n, z] gives the Bessel function of the second kind Y_n (z).

FourierCosCoefficient (Built-in Mathematica Symbol)

FourierCosCoefficient[expr, t, n] gives the n\[Null]^th coefficient in the Fourier cosine series expansion of expr.FourierCosCoefficient[expr, {t_1, t_2, ...}, {n_1, n_2, ...