Edexcel C1 — Question 6 4 marks

Exam BoardEdexcel
ModuleC1 (Core Mathematics 1)
Marks4
PaperDownload PDF ↗
TopicIndices and Surds
TypeRationalize denominator simple
DifficultyEasy -1.3 This is a routine C1 surds question testing standard techniques: (a) recognizes difference of two squares pattern giving 16-3=13, and (b) applies rationalizing the denominator by multiplying by conjugate. Both parts are direct applications of textbook methods with no problem-solving required, making it easier than average but not trivial since students must execute the rationalization correctly.
Spec1.02b Surds: manipulation and rationalising denominators

  1. Expand and simplify \((4 + \sqrt{3})(4 - \sqrt{3})\). [2]
  2. Express \(\frac{26}{4 + \sqrt{3}}\) in the form \(a + b\sqrt{3}\), where \(a\) and \(b\) are integers. [2]

\begin{enumerate}[label=(\alph*)]
\item Expand and simplify $(4 + \sqrt{3})(4 - \sqrt{3})$. [2]
\item Express $\frac{26}{4 + \sqrt{3}}$ in the form $a + b\sqrt{3}$, where $a$ and $b$ are integers. [2]
\end{enumerate}

\hfill \mbox{\textit{Edexcel C1  Q6 [4]}}