AQA Paper 1 2018 June — Question 15

Exam BoardAQA
ModulePaper 1 (Paper 1)
Year2018
SessionJune
TopicDifferentiation from First Principles

15 A curve has equation \(y = x ^ { 3 } - 48 x\) The point \(A\) on the curve has \(x\) coordinate - 4
The point \(B\) on the curve has \(x\) coordinate \(- 4 + h\)
15
  1. Show that the gradient of the line \(A B\) is \(h ^ { 2 } - 12 h\)
    15
  2. Explain how the result of part (a) can be used to show that \(A\) is a stationary point on the curve.
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