OCR MEI Further Pure Core AS 2024 June — Question 5 6 marks

Exam BoardOCR MEI
ModuleFurther Pure Core AS (Further Pure Core AS)
Year2024
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicRoots of polynomials
TypeSymmetric functions of roots
DifficultyModerate -0.5 This question tests routine matrix operations: computing a 3×3 determinant (part a), recalling that combined transformations multiply matrices (part b(i)), and using the property that det(PQ) = det(P)det(Q) with given constraints (part b(ii)). All parts are standard textbook exercises requiring recall and basic algebraic manipulation, with no problem-solving insight needed. Slightly easier than average due to straightforward application of formulas.
Spec4.03j Determinant 3x3: calculation4.03k Determinant 3x3: volume scale factor4.03m det(AB) = det(A)*det(B)

5
  1. Find the volume scale factor of the transformation with associated matrix \(\left( \begin{array} { r r r } 1 & 2 & 0 \\ 0 & 3 & - 1 \\ - 1 & 0 & 2 \end{array} \right)\).
  2. The transformations S and T of the plane have associated \(2 \times 2\) matrices \(\mathbf { P }\) and \(\mathbf { Q }\) respectively.
    1. Write down an expression for the associated matrix of the combined transformation S followed by T. The determinant of \(\mathbf { P }\) is 3 and \(\mathbf { Q } = \left( \begin{array} { r r } k & 3 \\ - 1 & 2 \end{array} \right)\), where \(k\) is a constant.
    2. Given that this combined transformation preserves both orientation and area, determine the value of \(k\).

Question 5:
AnswerMarks Guidance
5(a) det = 8
volume scale factor = 8B1
B1ft
AnswerMarks
[2]1.1a
1.1soi BC
ft their determinant value
AnswerMarks Guidance
5(b) (i)
[1]1.1 𝑘 3
Allow ( )𝐏
−1 2
AnswerMarks Guidance
5(b) (ii)
3(2k + 3) = 1
AnswerMarks
 k = − 43B1
M1
A1
AnswerMarks
[3]1.1
1.1
AnswerMarks
1.1soi
3  their (2k + 3) = 1 oe, e.g. 2k + 3 = 1/3
Question 5:
5 | (a) | det = 8
volume scale factor = 8 | B1
B1ft
[2] | 1.1a
1.1 | soi BC
ft their determinant value
5 | (b) | (i) | QP | B1
[1] | 1.1 | 𝑘 3
Allow ( )𝐏
−1 2
5 | (b) | (ii) | det(Q) = 2k + 3
3(2k + 3) = 1
 k = − 43 | B1
M1
A1
[3] | 1.1
1.1
1.1 | soi
3  their (2k + 3) = 1 oe, e.g. 2k + 3 = 1/3
5
\begin{enumerate}[label=(\alph*)]
\item Find the volume scale factor of the transformation with associated matrix $\left( \begin{array} { r r r } 1 & 2 & 0 \\ 0 & 3 & - 1 \\ - 1 & 0 & 2 \end{array} \right)$.
\item The transformations S and T of the plane have associated $2 \times 2$ matrices $\mathbf { P }$ and $\mathbf { Q }$ respectively.
\begin{enumerate}[label=(\roman*)]
\item Write down an expression for the associated matrix of the combined transformation S followed by T.

The determinant of $\mathbf { P }$ is 3 and $\mathbf { Q } = \left( \begin{array} { r r } k & 3 \\ - 1 & 2 \end{array} \right)$, where $k$ is a constant.
\item Given that this combined transformation preserves both orientation and area, determine the value of $k$.
\end{enumerate}\end{enumerate}

\hfill \mbox{\textit{OCR MEI Further Pure Core AS 2024 Q5 [6]}}