Variables \(x\) and \(y\) are such that \(\displaystyle y=\frac{\ln(2x^2-3)}{3x}\).

(a) Find \(\displaystyle \frac{dy}{dx}\).

(b) Hence find the approximate change in \(y\) when \(x\) increases from 2 to \(2+h\), where \(h\) is small.

(c) At the instant when \(x=2\), \(y\) is increasing at the rate of 4 units per second. Find the corresponding rate of increase in \(x\).