| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Binomial Theorem (positive integer n) |
| Type | Ratio of coefficients condition |
| Difficulty | Moderate -0.3 This is a straightforward binomial theorem question requiring standard application of the formula and solving a simple equation. Part (a) is routine recall, part (b) involves setting up and solving a linear equation from the coefficient ratio, and part (c) is direct substitution. The algebraic manipulation is minimal and the problem follows a standard textbook pattern with no novel insight required. |
| Spec | 1.04a Binomial expansion: (a+b)^n for positive integer n |
\begin{enumerate}
\item (a) Write down the first four terms of the binomial expansion, in ascending powers of $x$, of $( 1 + 3 x ) ^ { n }$, where $n > 2$.
\end{enumerate}
Given that the coefficient of $x ^ { 3 }$ in this expansion is ten times the coefficient of $x ^ { 2 }$,\\
(b) find the value of $n$,\\
(c) find the coefficient of $x ^ { 4 }$ in the expansion.\\
\hfill \mbox{\textit{Edexcel C2 Q1 [6]}}