Edexcel F1 2023 June — Question 9 5 marks

Exam BoardEdexcel
ModuleF1 (Further Pure Mathematics 1)
Year2023
SessionJune
Marks5
PaperDownload PDF ↗
TopicProof by induction
TypeProve divisibility
DifficultyStandard +0.3 This is a standard Further Maths induction proof for divisibility. While it requires proper induction structure (base case, assumption, inductive step), the algebra is straightforward: factoring out 4^k from 4^(k+1) and manipulating 6(k+1) to show divisibility by 18. It's slightly easier than average because divisibility proofs follow a well-practiced template and the arithmetic manipulation is routine for Further Maths students.
Spec4.01a Mathematical induction: construct proofs

  1. Prove, by induction, that for \(n \in \mathbb { Z } , n \geqslant 2\)
$$4 ^ { n } + 6 n - 10$$ is divisible by 18

\begin{enumerate}
  \item Prove, by induction, that for $n \in \mathbb { Z } , n \geqslant 2$
\end{enumerate}

$$4 ^ { n } + 6 n - 10$$

is divisible by 18

\hfill \mbox{\textit{Edexcel F1 2023 Q9 [5]}}