\(\(\(
\)\(\(beta =  .1;\)

    \(delta =  .3*π;\)

    \(A = 1.0;\)

    \(omeg0 = 1.0;\)

    \(omeg1 = Sqrt[omeg0^2 - beta^2];\)

    \(tR = 2  π/omeg0;\)

    \(tR = Log[200]/beta;\)

    \(dec = A;\)

    \(osc = A;\)

    \(x = dec*osc/A;\)

    \(Plot[{dec, \(-dec\), osc, x}, {t, 0, tR}, PlotPoints -> 100, 
        PlotLabel -> "Problem 3-23", AspectRatio ->  .45, 
        AxesLabel -> {"t", "x"}, 
        PlotStyle -> {Dashing[{ .005,  .01}], Dashing[{ .005,  .01}], 
            Dashing[{ .001,  .01}], Dashing[{1, 0}]}];\)\)\)\)