Paper 1 · Sequences and Series
⏱ Tested in 1 exam question since 2025
Lesson 13 of 15
Sequences and Series 10: Prove the Sum of Geometric Series by induction
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- Prove Sₙ = a(1−Rⁿ)/(1−R) for a geometric series by induction
- Apply the 4-step recipe: base case n = 1, assume P(k), prove P(k+1), conclude
- Use rule 1 of indices (aRᵏ·R = aRᵏ⁺¹) to finish the inductive step
- Write the formal closing line by the principle of induction
Most recent exam questions
- 2025 Paper 1 Q10(e)(ii) — mathematical induction
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