Find the responses of systems governed by the following equations of motion for the initial conditions \(x(0)=0, \dot{x}(0)=1\) :

a. \(2 \ddot{x}+8 \dot{x}+16 x=0\)

b. \(3 \ddot{x}+12 \dot{x}+9 x=0\)

c. \(2 \ddot{x}+8 \dot{x}+8 x=0\)