OCR MEI FP2 2009 June — Question 1

Exam BoardOCR MEI
ModuleFP2 (Further Pure Mathematics 2)
Year2009
SessionJune
TopicTaylor series
TypeDeduce related series from given series

1
    1. Use the Maclaurin series for \(\ln ( 1 + x )\) and \(\ln ( 1 - x )\) to obtain the first three non-zero terms in the Maclaurin series for \(\ln \left( \frac { 1 + x } { 1 - x } \right)\). State the range of validity of this series.
    2. Find the value of \(x\) for which \(\frac { 1 + x } { 1 - x } = 3\). Hence find an approximation to \(\ln 3\), giving your answer to three decimal places.
  1. A curve has polar equation \(r = \frac { a } { 1 + \sin \theta }\) for \(0 \leqslant \theta \leqslant \pi\), where \(a\) is a positive constant. The points on the curve have cartesian coordinates \(x\) and \(y\).
    1. By plotting suitable points, or otherwise, sketch the curve.
    2. Show that, for this curve, \(r + y = a\) and hence find the cartesian equation of the curve.
    3. Obtain the characteristic equation for the matrix \(\mathbf { M }\) where $$\mathbf { M } = \left( \begin{array} { r r r } 3 & 1 & - 2
      0 & - 1 & 0
      2 & 0 & 1 \end{array} \right)$$ Hence or otherwise obtain the value of \(\operatorname { det } ( \mathbf { M } )\).
    4. Show that - 1 is an eigenvalue of \(\mathbf { M }\), and show that the other two eigenvalues are not real. Find an eigenvector corresponding to the eigenvalue - 1 .
      Hence or otherwise write down the solution to the following system of equations. $$\begin{aligned} 3 x + y - 2 z & = - 0.1
      - y & = 0.6
      2 x + z & = 0.1 \end{aligned}$$
    5. State the Cayley-Hamilton theorem and use it to show that $$\mathbf { M } ^ { 3 } = 3 \mathbf { M } ^ { 2 } - 3 \mathbf { M } - 7 \mathbf { I }$$ Obtain an expression for \(\mathbf { M } ^ { - 1 }\) in terms of \(\mathbf { M } ^ { 2 } , \mathbf { M }\) and \(\mathbf { I }\).
    6. Find the numerical values of the elements of \(\mathbf { M } ^ { - 1 }\), showing your working.