| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Topic | Binomial Theorem (positive integer n) |
| Type | Find constants from coefficient conditions on terms |
| Difficulty | Moderate -0.8 This is a straightforward C2 binomial expansion question requiring routine application of the formula (1+px)^9 = 1 + 9px + 36p²x² + ... Part (a) is direct recall, part (b) involves simple algebra to find p=4 from 9p=36, then q=36p²=576. Below average difficulty as it's a standard textbook exercise with no problem-solving insight needed. |
| Spec | 1.04a Binomial expansion: (a+b)^n for positive integer n |
\begin{enumerate}[label=(\alph*)]
\item Find the first 3 terms, in ascending powers of $x$, of the binomial expansion of
$(1 + px)^9$,
where $p$ is a constant.
[2]
\end{enumerate}
The first 3 terms are 1, 36x and $qx^2$, where $q$ is a constant.
\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Find the value of $p$ and the value of $q$.
[4]
\end{enumerate}
\hfill \mbox{\textit{Edexcel C2 Q2 [6]}}