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A-LevelFurther MathematicsProof by InductionMay/June 2015Paper 1 Q37 Marks

The sequence a1, a2, a3, ... is such that a₁ > 5 and an+1 = 4an/5 + 5/an for every positive integer n. Prove by mathematical induction that a„ > 5 for every positive integer n. Prove also that an > an+1 for every positive integer n.

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The correct answer is . This question tests the candidate's understanding of proof by induction within the Further Mathematicssyllabus. The examiner's mark scheme requires...

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About This A-Level Further Mathematics Question

This structured question appeared in the Cambridge A-Level Further Mathematics (9231) May/June 2015 examination, Paper 1 Variant 2. It tests the topic of Proof by Induction and is worth 7 marks.

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