kill(all);

x(t):=C1*cos(k*t)+C2*sin(k*t)+c*a/(m*k^2);

diff(x(t),t);

dx(t):=C2*k*cos(k*t)-C1*k*sin(k*t);

a:0.1$
m:0.01$
ω:10$
c:3$

k:sqrt(c/m-ω^2);

solve([x(0)=a,dx(0)=0],[C1,C2]);

C1:-1/20$
C2:0$

wxplot2d([x(t)], [t,0,2],[y,0,0.2],[xlabel,"t,c"],[ylabel,"x, м"])$

wxplot2d([dx(t)], [t,0,2],[xlabel,"t,c"],[ylabel,"V, м/c"])$

wxplot2d([parametric,x(t),dx(t), [t,0,2]],[xlabel,"x,м"],[ylabel,"V, м/c"])$