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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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Glossary

equation

A statement that two mathematical expressions are equal.

union

The union of two sets A and B is the set containing all the elements of A and B.

Full Glossary List

This question appears in the following syllabi:

SyllabusModuleSectionTopic
Core PureComplex NumbersDe Moivre Theorem
AQA A-Level (UK - Pre-2017)FP2Complex NumbersDe Moivre theorem
AQA A2 Further Maths 2017Pure MathsFurther Complex NumbersDe Moivre Theorem
AQA AS/A2 Further Maths 2017Pure MathsFurther Complex NumbersDe Moivre Theorem
CCEA A-Level (NI)FP2Complex NumbersDe Moivre theorem
CIE A-Level (UK)P3Complex NumbersDe Moivre theorem
Edexcel A-Level (UK - Pre-2017)FP2Complex NumbersDe Moivre theorem
Edexcel A2 Further Maths 2017Core Pure MathsComplex NumbersDe Moivre Theorem
Edexcel AS/A2 Further Maths 2017Core Pure MathsComplex NumbersDe Moivre Theorem
I.B. Higher Level1Complex NumbersDe Moivre theorem
Methods (UK)M3Complex NumbersDe Moivre theorem
OCR A-Level (UK - Pre-2017)FP3Complex NumbersDe Moivre theorem
OCR A2 Further Maths 2017Pure CoreFurther Complex NumbersDe Moivre Theorem
OCR MEI A2 Further Maths 2017Core Pure BComplex NumbersDe Moivre Theorem
OCR-MEI A-Level (UK - Pre-2017)FP2Complex NumbersDe Moivre theorem
Scottish Advanced HighersM2Complex NumbersDe Moivre theorem
Scottish (Highers + Advanced)AM2Complex NumbersDe Moivre theorem
Universal (all site questions)CComplex NumbersDe Moivre theorem
WJEC A-Level (Wales)FP2Complex NumbersDe Moivre theorem