3 The graph shows part of the function \(y = a \ln ( b x )\).
\includegraphics[max width=\textwidth, alt={}, center]{2f403099-2813-40d8-a9ae-1f7e64d41f80-2_377_762_900_685}
The graph passes through the points \(( 2,0 )\) and \(( 4,1 )\).
- Show that \(b = \frac { 1 } { 2 }\) and find the exact value of \(a\).
- Solve the inequality \(| a \ln ( b x ) | < 2\).