OCR MEI C2 2010 January — Question 6 5 marks

Exam BoardOCR MEI
ModuleC2 (Core Mathematics 2)
Year2010
SessionJanuary
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicArithmetic Sequences and Series
TypeFind term or common difference
DifficultyEasy -1.3 This question tests basic recall of arithmetic and geometric sequence formulas with no problem-solving required. Part (i) is a straightforward arithmetic sequence requiring the formula u_n = u_1 + (n-1)d. Part (ii) is a standard geometric series sum to infinity with clearly given terms where students simply identify r = 0.4 and apply S_∞ = a/(1-r). Both parts are routine textbook exercises well below average A-level difficulty.
Spec1.04h Arithmetic sequences: nth term and sum formulae1.04j Sum to infinity: convergent geometric series |r|<1

  1. Find the 51st term of the sequence given by $$u_1 = 5,$$ $$u_{n+1} = u_n + 4.$$ [3]
  2. Find the sum to infinity of the geometric progression which begins $$5 \quad 2 \quad 0.8 \quad \ldots .$$ [2]

\begin{enumerate}[label=(\roman*)]
\item Find the 51st term of the sequence given by
$$u_1 = 5,$$
$$u_{n+1} = u_n + 4.$$ [3]

\item Find the sum to infinity of the geometric progression which begins
$$5 \quad 2 \quad 0.8 \quad \ldots .$$ [2]
\end{enumerate}

\hfill \mbox{\textit{OCR MEI C2 2010 Q6 [5]}}