OCR FP3 2014 June — Question 6

Exam BoardOCR
ModuleFP3 (Further Pure Mathematics 3)
Year2014
SessionJune
TopicVectors: Cross Product & Distances

6 The line \(l\) has equations \(\frac { x - 1 } { 2 } = \frac { y + 2 } { 3 } = \frac { z - 7 } { 5 }\). The plane \(\Pi\) has equation \(4 x - y - z = 8\).
  1. Show that \(l\) is parallel to \(\Pi\) but does not lie in \(\Pi\).
  2. The point \(A ( 1 , - 2,7 )\) is on \(l\). Write down a vector equation of the line through \(A\) which is perpendicular to \(\Pi\). Hence find the position vector of the point on \(\Pi\) which is closest to \(A\).
  3. Hence write down a vector equation of the line in \(\Pi\) which is parallel to \(l\) and closest to it.