\[\frac{3 - 2a^{\backslash a}}{2a} - \frac{1 - {a^{2}}^{\backslash 2}}{a^{2}} =\]
\[= \frac{3 - 2a^{2} - 2 + 2a^{2}}{2a^{2}} = \frac{1}{2a^{2}}.\]