It looks like you're trying to represent a mathematical expression. However, the notation you used is a bit unclear. If you meant to write a fraction or a division, it would typically be represented as:

\[
\frac{3x + 1}{2x - 1}
\]

This expression represents the division of \(3x + 1\) by \(2x - 1\).

If you have a specific question about this expression, such as simplifying it, finding its value for a particular \(x\), or solving an equation involving this expression, please provide more details!