Moderate -0.8 This is a straightforward algebraic simplification requiring factorisation of both numerator and denominator, then cancelling common factors. It's a routine C4 skill with no problem-solving element—students either recognise the factorisation or they don't. Below average difficulty due to being purely procedural with clear method.
It is given that
$$f(x) = \frac{x^2 + 2x - 24}{x^2 - 4x} \quad \text{for } x \neq 0, x \neq 4.$$
Express $f(x)$ in its simplest form. [3]
\hfill \mbox{\textit{OCR C4 2007 Q1 [3]}}