CAIE P1 2015 June — Question 2

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2015
SessionJune
TopicArea Under & Between Curves

2
\includegraphics[max width=\textwidth, alt={}, center]{c8925c7a-cb3b-43b8-9d09-8adc800c6887-2_627_828_641_657} The diagram shows the curve \(y = 2 x ^ { 2 }\) and the points \(X ( - 2,0 )\) and \(P ( p , 0 )\). The point \(Q\) lies on the curve and \(P Q\) is parallel to the \(y\)-axis.
  1. Express the area, \(A\), of triangle \(X P Q\) in terms of \(p\). The point \(P\) moves along the \(x\)-axis at a constant rate of 0.02 units per second and \(Q\) moves along the curve so that \(P Q\) remains parallel to the \(y\)-axis.
  2. Find the rate at which \(A\) is increasing when \(p = 2\).