OCR C3 2011 January — Question 8

Exam BoardOCR
ModuleC3 (Core Mathematics 3)
Year2011
SessionJanuary
TopicReciprocal Trig & Identities

8
    1. Sketch the graph of \(y = \operatorname { cosec } x\) for \(0 < x < 4 \pi\).
    2. It is given that \(\operatorname { cosec } \alpha = \operatorname { cosec } \beta\), where \(\frac { 1 } { 2 } \pi < \alpha < \pi\) and \(2 \pi < \beta < \frac { 5 } { 2 } \pi\). By using your sketch, or otherwise, express \(\beta\) in terms of \(\alpha\).
    1. Write down the identity giving \(\tan 2 \theta\) in terms of \(\tan \theta\).
    2. Given that \(\cot \phi = 4\), find the exact value of \(\tan \phi \cot 2 \phi \tan 4 \phi\), showing all your working.