The product of \(2\pi\) and \(\frac{3}{4}\) is
\[ 2\pi \times \frac{3}{4} = \frac{3\pi}{2}. \]
Since \(\pi\) is an irrational number, and the product of a non-zero rational number (\(\frac{3}{2}\)) and an irrational number (\(\pi\)) is always irrational, \(\frac{3\pi}{2}\) is irrational.