| Exam Board | Edexcel |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Topic | Indices and Surds |
| Type | Rationalize denominator simple |
| Difficulty | Moderate -0.8 This is a routine C1 surds question testing standard techniques: expanding brackets and rationalizing denominators. Both parts require straightforward algebraic manipulation with surds (recognizing √8 = 2√2) and simplification to the required form. While it requires care with arithmetic, it involves no problem-solving or novel insight—just direct application of well-practiced methods. |
| Spec | 1.02b Surds: manipulation and rationalising denominators |
Giving your answers in the form $a + b\sqrt{2}$, where $a$ and $b$ are rational numbers, find
\begin{enumerate}[label=(\alph*)]
\item $(3 - \sqrt{8})^2$, [3]
\item $\frac{1}{4 - \sqrt{8}}$. [3]
\end{enumerate}
\hfill \mbox{\textit{Edexcel C1 Q40 [6]}}