| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Topic | Binomial Theorem (positive integer n) |
| Type | Numerical approximation using expansion |
| Difficulty | Moderate -0.8 This is a straightforward binomial expansion question requiring direct application of the formula for the first four terms, followed by a routine substitution. Part (a) is mechanical calculation with no conceptual challenge, and part (b) is a standard textbook application. The question is easier than average A-level material due to its purely procedural nature with no problem-solving or insight required. |
| Spec | 1.04a Binomial expansion: (a+b)^n for positive integer n |
\begin{enumerate}[label=(\alph*)]
\item Find the first 4 terms of the expansion of $\left(1 + \frac{x}{3}\right)^{18}$ in ascending powers of $x$, giving each term in its simplest form.
[4]
\item Use your expansion to estimate the value of $(1.005)^{18}$, giving your answer to 5 decimal places.
[3]
\end{enumerate}
\hfill \mbox{\textit{Edexcel C2 Q3 [7]}}