OCR Further Pure Core 2 2018 December — Question 2

Exam BoardOCR
ModuleFurther Pure Core 2 (Further Pure Core 2)
Year2018
SessionDecember
TopicLinear transformations

2 In this question you must show detailed reasoning. S is the 2-D transformation which is a stretch of scale factor 3 parallel to the \(x\)-axis. \(\mathbf { A }\) is the matrix which represents S .
  1. Write down \(\mathbf { A }\).
  2. By considering the transformation represented by \(\mathbf { A } ^ { - 1 }\), determine the matrix \(\mathbf { A } ^ { - 1 }\). Matrix \(\mathbf { B }\) is given by \(\mathbf { B } = \left( \begin{array} { c c } 0 & - 1
    - 1 & 0 \end{array} \right)\). T is the transformation represented by \(\mathbf { B }\).
  3. Describe T.
  4. Determine the matrix which represents the transformation S followed by T .
  5. Demonstrate, by direct calculation, that \(( \mathbf { B A } ) ^ { - 1 } = \mathbf { A } ^ { - 1 } \mathbf { B } ^ { - 1 }\).