Edexcel P4 2020 October — Question 8

Exam BoardEdexcel
ModuleP4 (Pure Mathematics 4)
Year2020
SessionOctober
TopicVectors: Lines & Planes

8. Relative to a fixed origin \(O\), the lines \(l _ { 1 }\) and \(l _ { 2 }\) are given by the equations $$\begin{aligned} & l _ { 1 } : \quad \mathbf { r } = \left( \begin{array} { r } 4
- 3
2 \end{array} \right) + \lambda \left( \begin{array} { r } 3
- 2
- 1 \end{array} \right) \quad \text { where } \lambda \text { is a scalar parameter }
& l _ { 2 } : \quad \mathbf { r } = \left( \begin{array} { r } 2
0
- 9 \end{array} \right) + \mu \left( \begin{array} { r } 2
- 1
- 3 \end{array} \right) \quad \text { where } \mu \text { is a scalar parameter } \end{aligned}$$ Given that \(l _ { 1 }\) and \(l _ { 2 }\) meet at the point \(X\),
  1. find the position vector of \(X\). The point \(P ( 10 , - 7,0 )\) lies on \(l _ { 1 }\)
    The point \(Q\) lies on \(l _ { 2 }\)
    Given that \(\overrightarrow { P Q }\) is perpendicular to \(l _ { 2 }\)
  2. calculate the coordinates of \(Q\).