Consider the following function:
\[ f(x) = \begin{cases} k, & \text{if } x = 1 \\\frac{\sqrt{3x + 1} - \sqrt{2x + 2}}{x - 1}, & \text{if } x > -\frac{1}{3}, x \neq 1 \end{cases} \]
If \( f(x) \) is continuous at \( x = 1 \), the value of \( k \) (correct up to 2 decimal places) is