OCR FP3 — Question 5 10 marks

Exam BoardOCR
ModuleFP3 (Further Pure Mathematics 3)
Marks10
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVectors: Cross Product & Distances
TypeEquation of plane containing line and point/parallel to vector
DifficultyStandard +0.8 This FP3 question requires parametric representation of 3D lines, solving simultaneous equations to find intersection conditions, and computing a plane equation from two direction vectors. While systematic, it demands careful algebraic manipulation across multiple parameters and understanding of 3D vector geometry—more challenging than standard C3/C4 but typical for Further Maths content.
Spec4.04a Line equations: 2D and 3D, cartesian and vector forms4.04b Plane equations: cartesian and vector forms4.04e Line intersections: parallel, skew, or intersecting

Two lines have equations $$\frac{x-k}{2} = \frac{y+1}{-5} = \frac{z-1}{-3} \quad \text{and} \quad \frac{x-k}{1} = \frac{y+4}{-4} = \frac{z}{-2},$$ where \(k\) is a constant.
  1. Show that, for all values of \(k\), the lines intersect, and find their point of intersection in terms of \(k\). [6]
  2. For the case \(k = 1\), find the equation of the plane in which the lines lie, giving your answer in the form \(ax + by + cz = d\). [4]

Two lines have equations
$$\frac{x-k}{2} = \frac{y+1}{-5} = \frac{z-1}{-3} \quad \text{and} \quad \frac{x-k}{1} = \frac{y+4}{-4} = \frac{z}{-2},$$
where $k$ is a constant.

\begin{enumerate}[label=(\roman*)]
\item Show that, for all values of $k$, the lines intersect, and find their point of intersection in terms of $k$. [6]
\item For the case $k = 1$, find the equation of the plane in which the lines lie, giving your answer in the form $ax + by + cz = d$. [4]
\end{enumerate}

\hfill \mbox{\textit{OCR FP3  Q5 [10]}}