- In this question you must show all stages of your working. Solutions relying entirely on calculator technology are not acceptable.
Determine the values of \(x\) for which
$$64 \cosh ^ { 4 } x - 64 \cosh ^ { 2 } x - 9 = 0$$
Give your answers in the form \(q \ln 2\) where \(q\) is rational and in simplest form.