\[\boxed{\text{1043.\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\]
\[\textbf{а)}\ \frac{3x - 8}{12} > \frac{x - 1}{4}\ \ \ \ | \cdot 12\]
\[3x - 8 > 3x - 3\]
\[3x - 3x > - 3 + 8\]
\[0 > 5 \Longrightarrow \ \varnothing\ ни\ прикаком\ x.\]
\[\textbf{б)}\ \frac{x + 1}{3} < \frac{2x + 3}{6}\ \ \ | \cdot 6\]
\[2x + 2 < 2x + 3\]
\[2x - 2x < 3 - 2\]
\[0 < 1 \Longrightarrow \ x \in R \Longrightarrow \ то\ есть\ \]
\[при\ любом\ x.\]