Paper 1 · Complex Numbers ⏱ Tested in 5+ recent exam questions Lesson 13 of 17

Complex Numbers 13 – Converting to polar form and applying De Moivres theorem

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You’ll learn

  • Evaluate (a + bi)ⁿ by converting to polar form, applying De Moivre, then back to a + bi
  • Quadrant-adjust the argument correctly before raising to powers like (−√3 + i)⁷
  • Reduce oversized angles such as 35π/6 (mod 2π) before evaluating cos and sin
  • Verify small-power answers with a quick binomial expansion

Most recent exam questions

  • 2024 P1 Q2(b)
  • 2022 P1 Q1(b) — deferred
  • 2022 P1 Q3(b)
  • 2020 P1 Q2(b)(ii)
  • 2018 P1 Q4(b)

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