DirectedEdge[u, v] or u \[DirectedEdge] v represents a directed edge from u to v.

MatrixExp[m] gives the matrix exponential of m. MatrixExp[m, v] gives the matrix exponential of m applied to the vector v.

WignerD[{j, m_1, m_2}, \[Psi], \[Theta], \[Phi]] gives the Wigner D-function D_m_1^m_2, j(\[Psi], \[Theta], \[Phi]).WignerD[{j, m_1, m_2}, \[Theta], \[Phi]] gives the Wigner ...

PolynomialQuotient[p, q, x] gives the quotient of p and q, treated as polynomials in x, with any remainder dropped.

PlotStyle is an option for plotting and related functions that specifies styles in which objects are to be drawn.

DisplayForm[expr] prints with low-level boxes inside expr shown in explicit two-dimensional or other form.

MultiPoissonDistribution has been renamed to MultivariatePoissonDistribution and is part of the built-in Mathematica kernel. HotellingTSquareDistribution has been added to ...

Verbatim patterns. Here the x_ in the rule matches any expression. The Verbatim tells Mathematica that only the exact expression x_ should be matched.

In addition to its graphical results, Wolfram|Alpha can provide alternative representations that contain additional information or are well suited to particular tasks. These ...

Negative[x] gives True if x is a negative number.