MathsNet: C - Complex Numbers - Roots

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Page ID: 1769

C | Complex Numbers | De Moivre theorem | «Roots»

The equation z^n=a+ib \quad has n roots. We can use De Moivre's theorem to find them.
De Moivre's Theorem: (\cos \theta + i \sin \theta)^n = \cos n\theta + i \sin n\theta

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This question appears in the following syllabi:

Syllabus	Module	Section	Topic	Exam Year
AQA A-Level (UK - Pre-2017)	FP2	Complex Numbers	De Moivre theorem	-
AQA A2 Further Maths 2017	Pure Maths	Further Complex Numbers	De Moivre Theorem	-
AQA AS/A2 Further Maths 2017	Pure Maths	Further Complex Numbers	De Moivre Theorem	-
CCEA A-Level (NI)	FP2	Complex Numbers	De Moivre theorem	-
CIE A-Level (UK)	P3	Complex Numbers	De Moivre theorem	-
Edexcel A-Level (UK - Pre-2017)	FP2	Complex Numbers	De Moivre theorem	-
Edexcel A2 Further Maths 2017	Core Pure Maths	Complex Numbers	De Moivre Theorem	-
Edexcel AS/A2 Further Maths 2017	Core Pure Maths	Complex Numbers	De Moivre Theorem	-
I.B. Higher Level	1	Complex Numbers	De Moivre theorem	-
Methods (UK)	M3	Complex Numbers	De Moivre theorem	-
OCR A-Level (UK - Pre-2017)	FP3	Complex Numbers	De Moivre theorem	-
OCR A2 Further Maths 2017	Pure Core	Further Complex Numbers	De Moivre Theorem	-
OCR MEI A2 Further Maths 2017	Core Pure B	Complex Numbers	De Moivre Theorem	-
OCR-MEI A-Level (UK - Pre-2017)	FP2	Complex Numbers	De Moivre theorem	-
Scottish Advanced Highers	M2	Complex Numbers	De Moivre theorem	-
Scottish (Highers + Advanced)	AM2	Complex Numbers	De Moivre theorem	-
Universal (all site questions)	C	Complex Numbers	De Moivre theorem	-
WJEC A-Level (Wales)	FP2	Complex Numbers	De Moivre theorem	-