Paper 1 · Sequences and Series
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Lesson 11 of 15
Sequences and Series 8 : Geometric Sequences 4
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- Find the sum to infinity with S∞ = a/(1−r), checking the |r| < 1 condition
- Work a full amalgamation question: find a and r, then Tₙ, smallest n, Sₙ and S∞
- Bring n down from the power with logs when solving Tₙ < 0.01
- Reject any root with |r| ≥ 1 when the question gives you a sum to infinity
Most recent exam questions
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