\[\boxed{\text{6.233.}}\]
\[\textbf{а)}\ 7,8x = 7,8\]
\[x = 1.\ \]
\[\textbf{б)}\ 2,39x = 0\ \ \]
\[x = 0.\ \]
\[\textbf{в)}\ 5,8x = 58\ \]
\[x = 10.\ \]
\[\textbf{г)}\ n^{2} = n\ \ \ \]
\[n = 0\ или\ n = 1.\ \]
\[\textbf{д)}\ z^{3} = z\ \ \ \ \ \ \ \ \]
\[z = 0\ или\ z = 1.\ \]
\[\textbf{е)}\ p^{2} = p^{3}\text{\ \ \ \ }\]
\[\ p = 0\ или\ p = 1.\ \ \ \]