Let's find the inflection points, we'll need to solve the equation for this
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = 0$$
(the second derivative equals zero),
the roots of this equation will be the inflection points for the specified function graph:
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = $$
the second derivative$$\frac{4 \delta\left(2 x - 3\right) - \frac{\operatorname{sign}^{2}{\left(2 x - 3 \right)}}{\left|{2 x - 3}\right| - 2}}{\sqrt{\left|{2 x - 3}\right| - 2}} = 0$$
Solve this equationSolutions are not found,
maybe, the function has no inflections