OCR Further Pure Core 1 2020 November — Question 3 5 marks

Exam BoardOCR
ModuleFurther Pure Core 1 (Further Pure Core 1)
Year2020
SessionNovember
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
Topic3x3 Matrices
TypeTransformation mapping problems
DifficultyModerate -0.3 This is a straightforward Further Maths question testing basic 3D matrix operations: matrix powers (which reveals a pattern after A²), identifying a rotation from a matrix, writing down a simple reflection matrix, and applying it to a point. While 3D transformations are beyond standard A-level, these are routine exercises for Further Maths students with no novel problem-solving required.
Spec4.03a Matrix language: terminology and notation4.03b Matrix operations: addition, multiplication, scalar4.03f Linear transformations 3D: reflections and rotations about axes

3 You are given the matrix \(\mathbf { A } = \left( \begin{array} { c c c } 1 & 0 & 0 \\ 0 & 0 & 1 \\ 0 & - 1 & 0 \end{array} \right)\).
  1. Find \(\mathbf { A } ^ { 4 }\).
  2. Describe the transformation that \(\mathbf { A }\) represents. The matrix \(\mathbf { B }\) represents a reflection in the plane \(x = 0\).
  3. Write down the matrix \(\mathbf { B }\). The point \(P\) has coordinates (2, 3, 4). The point \(P ^ { \prime }\) is the image of \(P\) under the transformation represented by \(\mathbf { B }\).
  4. Find the coordinates of \(P ^ { \prime }\).

Question 3:
AnswerMarks Guidance
3(a) A4 = I
[1]
AnswerMarks
(b)Rotation
Clockwise 900 about x-axisB1
B12.2a
2.2aOr 2700 anticlockwise
Accept radians
[2]
AnswerMarks
(c)−1 0 0
 
0 1 0
 
 
AnswerMarks Guidance
 0 0 1B1 1.1
[1]
AnswerMarks Guidance
(d)(−2, 3, 4) B1
    
0 1 0 3 = 3
    
    
 0 0 14  4 
Allow vector as answer
[1]
Question 3:
3 | (a) | A4 = I | B1 | 1.1 | Accept 3×3 matrix
[1]
(b) | Rotation
Clockwise 900 about x-axis | B1
B1 | 2.2a
2.2a | Or 2700 anticlockwise
Accept radians
[2]
(c) | −1 0 0
 
0 1 0
 
 
 0 0 1 | B1 | 1.1 | All correct
[1]
(d) | (−2, 3, 4) | B1 | 1.1 | −1 0 02 −2
    
0 1 0 3 = 3
    
    
 0 0 14  4 
Allow vector as answer
[1]
3 You are given the matrix $\mathbf { A } = \left( \begin{array} { c c c } 1 & 0 & 0 \\ 0 & 0 & 1 \\ 0 & - 1 & 0 \end{array} \right)$.
\begin{enumerate}[label=(\alph*)]
\item Find $\mathbf { A } ^ { 4 }$.
\item Describe the transformation that $\mathbf { A }$ represents.

The matrix $\mathbf { B }$ represents a reflection in the plane $x = 0$.
\item Write down the matrix $\mathbf { B }$.

The point $P$ has coordinates (2, 3, 4). The point $P ^ { \prime }$ is the image of $P$ under the transformation represented by $\mathbf { B }$.
\item Find the coordinates of $P ^ { \prime }$.
\end{enumerate}

\hfill \mbox{\textit{OCR Further Pure Core 1 2020 Q3 [5]}}