Paper 1 · Complex Numbers
⏱ Tested in 5 exam questions since 2022
Lesson 12 of 17
Complex Numbers 12 – Introduction to De Moivres theorem
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- Apply De Moivre's theorem to raise polar-form complex numbers to integer powers
- Evaluate cos nθ and sin nθ in degrees or radians using page 13 of the tables
- Simplify each answer back to rectangular form a + bi with surd values like 1/√2
Most recent exam questions
- 2025 Paper 1 Q4(b) — de Moivre identity proof — expand (cos θ + i sin θ)² two different ways, equate real parts
- 2025 Paper 1 Q4(c) — finding roots of a complex equation via de Moivre — fractional-power route, multi-valued
- 2024 Paper 1 Q2(b) — raising a complex number to a high power via polar form + de Moivre
- 2022 Paper 1 Q1(b) — raise a complex number to a positive integer power using De Moivre's theorem — the four-…
- 2022 Paper 1 Q3(b) — raising a complex number to a high power via polar form + De Moivre
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