8.4. Find at least one solution to the equation $\left[x^{2}\right]-[x]^{2}=1993$ and verify it. Here $[A]$ denotes the greatest integer not exceeding $A$ (for example, $\left[-\frac{5}{2}\right]=-3,[\sqrt{2}]=1$).
$\begin{array}{l}\text { 8.4. For example } x=1993.5 \text {. } \\ \text { Given }\left[x^{2}\right]-[x]^{2}=1993 \\ \Rightarrow\left[2[x] \cdot\{x\}+\left\{\left.x\right|^{2}\right]=1993 \text {. }\right. \\ \text { where }\{x\}=x-[x] .\end{array}$