| Exam Board | WJEC |
|---|---|
| Module | Unit 1 (Unit 1) |
| Year | 2024 |
| Session | June |
| Marks | 9 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Binomial Theorem (positive integer n) |
| Type | Binomial times linear coefficient |
| Difficulty | Moderate -0.3 Part (a) is straightforward binomial expansion requiring recall of the formula and basic arithmetic. Part (b) requires coefficient matching after multiplying by (1+ax), which involves some algebraic manipulation but follows a standard pattern. The question is slightly easier than average due to being mostly procedural with clear steps, though part (b) requires careful bookkeeping of coefficients. |
| Spec | 1.04a Binomial expansion: (a+b)^n for positive integer n |
\begin{enumerate}[label=(\alph*)]
\item Write down the binomial expansion of $(2 - x)^6$ up to and including the term in $x^2$. [3]
\item Given that
$$(1 + ax)(2 - x)^6 = 64 + bx + 336x^2 + \ldots,$$
find the values of the constants $a$, $b$. [6]
\end{enumerate}
\hfill \mbox{\textit{WJEC Unit 1 2024 Q9 [9]}}