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Complex numbers formulae

The 2 results the complex numbers notes display, each with the conditions it needs to be true and a link to the lesson that states it. Of the 2, the formulae booklet prints 1 and 1 is yours to memorise.

Further Maths · 2 lessons with formulae.

A result the Edexcel formulae booklet prints is marked as such; one it does not print is marked to learn; and a result badged derived in the lesson is a working line the notes build in front of you rather than a standard result to memorise.

2 lessons

Modulus, argument and loci

z = r(\cos θ + \text{i} \sin θ)

NOT IN THE BOOKLET: LEARN ITConditionsr = |z| ≥ 0 and θ = arg z, conventionally taken in (−π, π].

De Moivre's theorem and trigonometric identities

(\cos θ + \text{i} \sin θ)^{n} = \cos nθ + \text{i} \sin nθ

IN THE FORMULAE BOOKLETConditionsn an integer. For fractional n the left-hand side has several values and the right-hand side gives only one of them.

Every formula in the library is indexed by unit on the equation index, and the complex numbers notes are where these results are derived and used. The one the booklet does not print is on the list of every formula to memorise, alongside the rest of the course.

Also: Further proof formulae · Further algebra and series formulae