To multiply the fractions \( \frac{3}{8} \) and \( \frac{1}{2} \), you multiply the numerators together and the denominators together.
- Multiply the numerators: \( 3 \times 1 = 3 \)
- Multiply the denominators: \( 8 \times 2 = 16 \)
So,
\[ \frac{3}{8} \times \frac{1}{2} = \frac{3}{16} \]
Thus, the answer in the form \([?]/[?]\) is \( \frac{3}{16} \).