AQA C1 2007 January — Question 1

Exam BoardAQA
ModuleC1 (Core Mathematics 1)
Year2007
SessionJanuary
TopicFactor & Remainder Theorem
TypeFind constant, factorise completely

1 The polynomial \(\mathrm { p } ( x )\) is given by $$\mathrm { p } ( x ) = x ^ { 3 } - 4 x ^ { 2 } - 7 x + k$$ where \(k\) is a constant.
    1. Given that \(x + 2\) is a factor of \(\mathrm { p } ( x )\), show that \(k = 10\).
    2. Express \(\mathrm { p } ( x )\) as the product of three linear factors.
  1. Use the Remainder Theorem to find the remainder when \(\mathrm { p } ( x )\) is divided by \(x - 3\).
  2. Sketch the curve with equation \(y = x ^ { 3 } - 4 x ^ { 2 } - 7 x + 10\), indicating the values where the curve crosses the \(x\)-axis and the \(y\)-axis. (You are not required to find the coordinates of the stationary points.)