OCR C1 2010 June — Question 3 5 marks

Exam BoardOCR
ModuleC1 (Core Mathematics 1)
Year2010
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicIndices and Surds
TypeRationalize denominator simple
DifficultyEasy -1.2 This is a straightforward C1 question testing standard techniques: rationalizing a denominator by multiplying by the conjugate, and simplifying surds by factoring. Both parts are routine textbook exercises requiring only direct application of well-practiced methods with no problem-solving or insight needed.
Spec1.02b Surds: manipulation and rationalising denominators

3
  1. Express \(\frac { 12 } { 3 + \sqrt { 5 } }\) in the form \(a - b \sqrt { 5 }\), where \(a\) and \(b\) are positive integers.
  2. Express \(\sqrt { 18 } - \sqrt { 2 }\) in simplified surd form.

3 (i) Express $\frac { 12 } { 3 + \sqrt { 5 } }$ in the form $a - b \sqrt { 5 }$, where $a$ and $b$ are positive integers.\\
(ii) Express $\sqrt { 18 } - \sqrt { 2 }$ in simplified surd form.

\hfill \mbox{\textit{OCR C1 2010 Q3 [5]}}