Edexcel AEA 2010 June — Question 2 11 marks

Exam BoardEdexcel
ModuleAEA (Advanced Extension Award)
Year2010
SessionJune
Marks11
PaperDownload PDF ↗
TopicArithmetic Sequences and Series
TypeTwo related arithmetic progressions
DifficultyChallenging +1.2 This is an AEA question requiring algebraic manipulation of arithmetic series formulas with symbolic parameters p and q rather than numerical values. While it demands careful algebraic work and solving simultaneous equations in terms of parameters, the approach is methodical using standard S_n = n/2[2a + (n-1)d] without requiring novel insight or proof techniques.
Spec1.04h Arithmetic sequences: nth term and sum formulae

2.The sum of the first \(p\) terms of an arithmetic series is \(q\) and the sum of the first \(q\) terms of the same arithmetic series is \(p\) ,where \(p\) and \(q\) are positive integers and \(p \neq q\) . Giving simplified answers in terms of \(p\) and \(q\) ,find
  1. the common difference of the terms in this series,
  2. the first term of the series,
  3. the sum of the first \(( p + q )\) terms of the series.

2.The sum of the first $p$ terms of an arithmetic series is $q$ and the sum of the first $q$ terms of the same arithmetic series is $p$ ,where $p$ and $q$ are positive integers and $p \neq q$ .

Giving simplified answers in terms of $p$ and $q$ ,find
\begin{enumerate}[label=(\alph*)]
\item the common difference of the terms in this series,
\item the first term of the series,
\item the sum of the first $( p + q )$ terms of the series.
\end{enumerate}

\hfill \mbox{\textit{Edexcel AEA 2010 Q2 [11]}}