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Mathematica Teacher's Edition

Built-in Functions

Algebraic Computation

Formula Manipulation

TrigExpand

TrigExpand[expr] expands out trigonometric functions in expr.

TrigExpand operates on both circular and hyperbolic functions.
TrigExpand splits up sums and integer multiples that appear in arguments of trigonometric functions, and then expands products of trigonometric functions into sums of powers, using trigonometric identities when possible.
See The Mathematica Book on the web: Section 1.4.5 and Section 3.3.7.
See also: TrigFactor, TrigReduce, TrigToExp, Expand, Simplify, FullSimplify.

Further Examples