Đáp án:
a. x>2
Giải thích các bước giải:
\(\begin{array}{l}
a.\frac{{4x - 5}}{3} > \frac{{7 - x}}{5}\\
\to \frac{{5\left( {4x - 5} \right) - 3\left( {7 - x} \right)}}{{15}} > 0\\
\to 20x - 25 - 21 + 3x > 0\\
\to 23x > 46\\
\to x > 2
\end{array}\)
\(\begin{array}{l}
b.\frac{{2x + 1}}{2} + 3 > \frac{{3 - 5x}}{3} - \frac{{4x + 1}}{4}\\
\to \frac{{6\left( {2x + 1} \right) + 12.3}}{{12}} > \frac{{4\left( {3 - 5x} \right) - 3\left( {4x + 1} \right)}}{{12}}\\
\to 12x + 6 + 36 - 12 + 20x + 12x + 3 > 0\\
\to 44x > - 33\\
\to x > - \frac{3}{4}
\end{array}\)
