\[|x - 1| + |x - 2| = 3\]
\[- (x - 1) - (x - 2) = 3\]
\[- x + 1 - x + 2 - 3 = 0\]
\[- 2x = 0\]
\[x = 0.\]
\[\ x - 1 - (x - 2) = 3\]
\[x - 1 - x + 2 - 3 = 0\]
\[- 2 = 0 \Longrightarrow \ \ нет\ решения.\]
\[x - 1 + x - 2 = 3\]
\[2x - 3 = 3\]
\[2x = 6\]
\[x = 3.\]
\[Ответ:0;3.\]