OCR C2 2014 June — Question 7

Exam BoardOCR
ModuleC2 (Core Mathematics 2)
Year2014
SessionJune
TopicFactor & Remainder Theorem
TypeStandard verify, factorise, solve

7 The cubic polynomial \(\mathrm { f } ( x )\) is defined by \(\mathrm { f } ( x ) = 12 - 22 x + 9 x ^ { 2 } - x ^ { 3 }\).
  1. Find the remainder when \(\mathrm { f } ( x )\) is divided by \(( x + 2 )\).
  2. Show that ( \(3 - x\) ) is a factor of \(\mathrm { f } ( x )\).
  3. Express \(\mathrm { f } ( x )\) as the product of a linear factor and a quadratic factor.
  4. Hence solve the equation \(\mathrm { f } ( x ) = 0\), giving each root in simplified surd form where appropriate.