One of the important features of Mathematica is its ability to give you exact, symbolic, results for computations. There are, however, computations where it is just ...
Assumptions is an option for functions such as Simplify, Refine, and Integrate that specifies default assumptions to be made about symbolic quantities.
NumberFieldNormRepresentatives[a, m] gives a list of representatives of classes of algebraic integers of norm \[PlusMinus]m in the field \[DoubleStruckCapitalQ][a] generated ...
TrigExpand[expr] expands out trigonometric functions in expr.
A "How to" describes how to carry out particular tasks with Mathematica, giving step-by-step instructions for common cases.
TrigReduce[expr] rewrites products and powers of trigonometric functions in expr in terms of trigonometric functions with combined arguments.
Collect
(Built-in Mathematica Symbol) Collect[expr, x] collects together terms involving the same powers of objects matching x. Collect[expr, {x_1, x_2, ...}] collects together terms that involve the same powers ...
Decompose[poly, x] decomposes a polynomial, if possible, into a composition of simpler polynomials.
FindInstance[expr, vars] finds an instance of vars that makes the statement expr be True. FindInstance[expr, vars, dom] finds an instance over the domain dom. Common choices ...
MathieuCPrime[a, q, z] gives the derivative with respect to z of the even Mathieu function with characteristic value a and parameter q.