De Moivre's Theorem ((cos θ + i sin θ)^n = cos nθ + i sin nθ)

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(cos θ + i sin θ)^n = cos nθ + i sin nθ

What each symbol means

SymbolWhat it stands for
nInteger (theorem extends to rational n with branch care for general z^n)
θReal angle

When to use this

Standard form for unit-modulus complex number. For (re^(iθ))^n = r^n e^(inθ).