Paper 1 · Sequences and Series ⏱ Tested in 2 exam questions since 2018 Lesson 10 of 15

Sequences and Series 7: Geometric Sequences 3

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You’ll learn

  • Derive Tₙ = ar⁽ⁿ⁻¹⁾ by spotting the pattern in successive terms
  • Find a and r from two given terms by substitution — divide the equations to remove a
  • Take cube or fifth roots to extract r (e.g. r³ = 27/8 ⟹ r = 3/2)
  • Divide by a fraction by flipping it and multiplying (8 ÷ 3/2 = 8 × 2/3)

Most recent exam questions

  • 2024 P1 Q5(b)
  • 2018 P1 Q9(b)(i)

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