| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Geometric Sequences and Series |
| Type | Find sum to infinity |
| Difficulty | Moderate -0.8 This is a straightforward geometric series question requiring standard formula application: finding r from ar^4/ar = 1.125/9, then finding a, then using S_∞ = a/(1-r). All steps are routine C2 content with no problem-solving insight needed, making it easier than average but not trivial due to the multi-step nature. |
| Spec | 1.04i Geometric sequences: nth term and finite series sum1.04j Sum to infinity: convergent geometric series |r|<1 |
| Answer | Marks | Guidance |
|---|---|---|
| 5 | 3.1 | 3 |
Question 5:
5 | 3.1 | 3 | 4 | 7The second and fifth terms of a geometric series are 9 and 1.125 respectively.
For this series find
\begin{enumerate}[label=(\alph*)]
\item the value of the common ratio, [3]
\item the first term, [2]
\item the sum to infinity. [2]
\end{enumerate}
\hfill \mbox{\textit{Edexcel C2 Q5 [7]}}