Figure $2$: Circuit for Problem $4.$

Problem $4$: Application$-15\backslash \%$

Consider the first order switched LR circuit shown in Figure $4.$ For a long time, the left switch has been closed and the right switch has been open. Then, the right switch is closed at $\backslash ($ t$=0\backslash )$ and the left switch is opened at $\backslash ($ t$=4\mathrm{.}4\backslash$mathrm$\{$~s$\}\backslash ).$ Find an expression for the inductor current, $\backslash ($ i$($t$)\backslash ),$ for all times $\backslash (0\backslash$leq t $\backslash ).$