OCR MEI FP1 2011 January — Question 2 7 marks

Exam BoardOCR MEI
ModuleFP1 (Further Pure Mathematics 1)
Year2011
SessionJanuary
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMatrices
TypeArea transformation under matrices
DifficultyModerate -0.3 This is a straightforward Further Maths question testing standard matrix transformation properties. Part (i) requires knowing that area scales by |det M| (det = 12, so area = 36). Part (ii) is routine matrix inversion. Part (iii) asks for conceptual understanding that det(M) × det(M⁻¹) = 1, representing inverse transformations cancelling. While this is Further Maths content, the calculations are mechanical and the concepts are core syllabus material, making it slightly easier than an average A-level question overall.
Spec4.03h Determinant 2x2: calculation4.03i Determinant: area scale factor and orientation4.03n Inverse 2x2 matrix

2 You are given that \(\mathbf { M } = \left( \begin{array} { r r } 4 & 0 \\ - 1 & 3 \end{array} \right)\).
  1. The transformation associated with \(\mathbf { M }\) is applied to a figure of area 3 square units. Find the area of the transformed figure.
  2. Find \(\mathbf { M } ^ { - 1 }\) and \(\operatorname { det } \mathbf { M } ^ { - 1 }\).
  3. Explain the significance of \(\operatorname { det } \mathbf { M } \times \operatorname { det } \mathbf { M } ^ { - 1 }\) in terms of transformations.

2 You are given that $\mathbf { M } = \left( \begin{array} { r r } 4 & 0 \\ - 1 & 3 \end{array} \right)$.\\
(i) The transformation associated with $\mathbf { M }$ is applied to a figure of area 3 square units. Find the area of the transformed figure.\\
(ii) Find $\mathbf { M } ^ { - 1 }$ and $\operatorname { det } \mathbf { M } ^ { - 1 }$.\\
(iii) Explain the significance of $\operatorname { det } \mathbf { M } \times \operatorname { det } \mathbf { M } ^ { - 1 }$ in terms of transformations.

\hfill \mbox{\textit{OCR MEI FP1 2011 Q2 [7]}}