\textbf{124-} What is the value of $\displaystyle\int_1^4 \sqrt{\left(\frac{1}{2}x^2 - \frac{1}{x}\right)^2 + 1}\,dx$? \medskip \hfill $4\ (1$ \hfill $5\ (2$ \hfill $6\ (3$ \hfill $7\ (4$ \bigskip