SPS SPS SM Pure 2023 September — Question 7

Exam BoardSPS
ModuleSPS SM Pure (SPS SM Pure)
Year2023
SessionSeptember
TopicFactor & Remainder Theorem
TypeTwo polynomials, shared factor or separate conditions

7.
\(( x - 3 )\) is a common factor of \(\mathrm { f } ( x )\) and \(\mathrm { g } ( x )\) where: $$\begin{aligned} & \mathrm { f } ( x ) = 2 x ^ { 3 } - 11 x ^ { 2 } + ( p - 15 ) x + q
& \mathrm {~g} ( x ) = 2 x ^ { 3 } - 17 x ^ { 2 } + p x + 2 q \end{aligned}$$
    1. Show that \(3 p + q = 90\) and \(3 p + 2 q = 99\) Fully justify your answer.
  1. (ii) Hence find the values of \(p\) and \(q\).
  2. \(\quad \mathrm { h } ( x ) = \mathrm { f } ( x ) + \mathrm { g } ( x )\) Using your values of \(p\) and \(q\), fully factorise \(\mathrm { h } ( x )\)