Suppose $a=c_1{e}^{-t}{c}_2{e}^t.$

a$.$ Verify that $x=c_1{e}^{-4}{c}_2{e}^{4t}$ is a solution to $x^{\text{'}\text{'}}-3x^{\text{'}}-4x=0$ by wibstituting it into the differential equation $($Inter the terms in the order given. Inter $c_1$ as $c)$ and $c_2$ as $c_2).$

$q,$

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$=0.$

b$.$ Find $x(t)$ if $x(0)=4$ and $x^{\text{'}}(0)=2.$

$x(t)=$

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help $($formulas$)$