Edexcel FP1 — Question 32 5 marks

Exam BoardEdexcel
ModuleFP1 (Further Pure Mathematics 1)
Marks5
PaperDownload PDF ↗
TopicProof by induction
TypeProve summation with exponentials
DifficultyStandard +0.3 This is a standard proof by induction for a summation formula. While it's Further Maths content, the structure is routine: verify base case, assume for n=k, prove for n=k+1 using algebraic manipulation. The algebra requires careful handling of powers of 2 but follows a predictable pattern. Slightly easier than average due to its formulaic nature, though the FP1 context means students should be comfortable with induction mechanics.
Spec1.04g Sigma notation: for sums of series4.01a Mathematical induction: construct proofs

Prove by induction that, for \(n \in \mathbb{Z}^+\), \(\sum_{r=1}^{n} r 2^r = 2\{1 + (n - 1)2^n\}\). [5]

Prove by induction that, for $n \in \mathbb{Z}^+$, $\sum_{r=1}^{n} r 2^r = 2\{1 + (n - 1)2^n\}$.
[5]

\hfill \mbox{\textit{Edexcel FP1  Q32 [5]}}