AQA Paper 1 2019 June — Question 12

Exam BoardAQA
ModulePaper 1 (Paper 1)
Year2019
SessionJune
TopicReciprocal Trig & Identities

12
  1. Show that the equation $$2 \cot ^ { 2 } x + 2 \operatorname { cosec } ^ { 2 } x = 1 + 4 \operatorname { cosec } x$$ can be written in the form $$a \operatorname { cosec } ^ { 2 } x + b \operatorname { cosec } x + c = 0$$ 12
  2. Hence, given \(x\) is obtuse and $$2 \cot ^ { 2 } x + 2 \operatorname { cosec } ^ { 2 } x = 1 + 4 \operatorname { cosec } x$$ find the exact value of \(\tan x\) Fully justify your answer.
    13A curve, \(C\), has equation
    \(y = \frac { \mathrm { e } ^ { 3 x - 5 } } { x ^ { 2 } }\)
    Show that \(C\) has exactly one stationary point.
    Fully justify your answer.
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