OCR C2 2010 June — Question 1 5 marks

Exam BoardOCR
ModuleC2 (Core Mathematics 2)
Year2010
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicFactor & Remainder Theorem
TypeSingle unknown constant
DifficultyModerate -0.8 This is a straightforward application of the factor theorem requiring substitution of x=2 to find a constant, followed by a routine remainder theorem calculation. Both parts are standard textbook exercises with no problem-solving insight needed, making it easier than average but not trivial since it requires correct algebraic manipulation across two parts.
Spec1.02j Manipulate polynomials: expanding, factorising, division, factor theorem

1 The cubic polynomial \(\mathrm { f } ( x )\) is defined by \(\mathrm { f } ( x ) = x ^ { 3 } + a x ^ { 2 } - a x - 14\), where \(a\) is a constant.
  1. Given that \(( x - 2 )\) is a factor of \(\mathrm { f } ( x )\), find the value of \(a\).
  2. Using this value of \(a\), find the remainder when \(\mathrm { f } ( x )\) is divided by ( \(x + 1\) ).

1 The cubic polynomial $\mathrm { f } ( x )$ is defined by $\mathrm { f } ( x ) = x ^ { 3 } + a x ^ { 2 } - a x - 14$, where $a$ is a constant.\\
(i) Given that $( x - 2 )$ is a factor of $\mathrm { f } ( x )$, find the value of $a$.\\
(ii) Using this value of $a$, find the remainder when $\mathrm { f } ( x )$ is divided by ( $x + 1$ ).

\hfill \mbox{\textit{OCR C2 2010 Q1 [5]}}