Laplace transform of $f(t)=\frac{\sin(t)}t$ for $t>0$, $f(t)=0$ for $t \le 0$

From Wikipedia we have: The Laplace transform of a function $f(t)$, defined for all real numbers $t \ge 0$, is the function $F(s)$, which is a unilateral transform [ emphasis by us ] defined by $$ F(s) = \int_0^\infty f(t)e^{-st}\,dt $$ The unilateral transform ($t \ge 0$) of the sine is (table @ Wikipedia): $$ \sin(\omega t)\cdot u(t) \; \to \; \frac{\omega}{s^2+\omega^2} \quad \Longrightarrow \quad \sin(t)\cdot u(t) \; \to \; \frac{1}{1+s^2} $$ Where the Heaviside step function $u(t)$ is defined by: $$ u(t) = \begin{cases} 0 & \mbox{for} & t < 0\\ 1 & \mbox{for} & t \ge 0\end{cases} $$ The unilateral transform ($t \ge 0$) of a function $f(t)/t$ is (table @ Wikipedia): $$ \frac{1}{t}f(t) \; \to \; \int_s^\infty F(\sigma)\,d\sigma $$ Combining these: $$ f(t) = \frac{\sin(t)}{t}\cdot u(t) \; \to \; \int_s^\infty \frac{d\sigma}{1+\sigma^2} = \left[\arctan(\sigma)\right]_s^\infty = \frac{\pi}{2}-\arctan(s) = F(s) $$ Forget about the rule $\;G(s)=F(s) \ e^{-sa}\;$, because for $\,a=0\,$ it adds nothing new here : $G(s)=F(s) \ e^{-s0} = F(s)$ .