(Calculus) Let the function $f(x)$ be defined as
$$f(x) = \int_a^x \{2 + \sin(t^2)\} dt$$
If $f''(a) = \sqrt{3}a$, find the value of $(f^{-1})'(0)$.\\
(Given: $a$ is a constant satisfying $0 < a < \sqrt{\frac{\pi}{2}}$) [4 points]\\
(1) $\frac{1}{10}$\\
(2) $\frac{1}{5}$\\
(3) $\frac{3}{10}$\\
(4) $\frac{2}{5}$\\
(5) $\frac{1}{2}$