A curve has equation
$$y = \frac{4x - 3a}{2(x^2 + a^2)},$$
where \(a\) is a positive constant.
- Explain why the curve has no asymptotes parallel to the \(y\)-axis. [2]
- Find, in terms of \(a\), the set of values of \(y\) for which there are no points on the curve. [5]
- Find the exact value of \(\int_a^{2a} \frac{4x - 3a}{2(x^2 + a^2)} dx\), showing that it is independent of \(a\). [5]