Question $12$

Find $L\{f(t)\}$ for $f(t)=\{\begin{array}{cc}0,& 0t<mfrac><mrow><mi></mi></mrow><mrow><mn>2</mn></mrow></mfrac>\\ cost,& t\frac{}{2}\end{array}.$

$\frac{s}{s^2+1}{e}^{-\frac{s}{2}},s>0$

$-\frac{s}{s^2+1}{e}^{-\frac{s}{2}},s>0$

$\frac{1}{s^2+1}{e}^{-\frac{s}{2}},s>0$

$-\frac{1}{s^2+1}{e}^{-\frac{s}{2}},s>\frac{}{2}$

$-\frac{1}{s^2+1}{e}^{-\frac{s}{2}},s>0$