| Exam Board | OCR |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Indices and Surds |
| Type | Rationalize denominator simple |
| Difficulty | Easy -1.2 This is a straightforward rationalize-the-denominator question requiring multiplication by the conjugate (3√5 - 7) and simplification. It's a standard C1 technique with no problem-solving required, making it easier than average, though slightly more involved than basic index law recall. |
| Spec | 1.02b Surds: manipulation and rationalising denominators |
\begin{enumerate}
\item Express
\end{enumerate}
$$\frac { 2 } { 3 \sqrt { 5 } + 7 }$$
in the form $a + b \sqrt { 5 }$ where $a$ and $b$ are rational.\\
\hfill \mbox{\textit{OCR C1 Q2 [3]}}