HOW TO PLOT A GRAPH FOR THIS PROGRAM?

HELLO DEAR ALL,

I REALLY NEED HELP IN COMPLETING THIS PROGRAM,AS I WISHED TO PLOT A GRAPH OF STATE-TIME,WITH VARIABLES x1,x2,and u presented.

THANK YOU VERY MUCH IN ADVANCE FOR SUGGESTIONS,COMMENTS,ADVICES...

HER IS THE PROGRAM THAT NEEDS TO BE FINISHED BY PLOT:

%State equations
syms x1 x2 p1 p2 u;
Dx1=-x2+u;
Dx2=x2;

%Cost functiuon inside the integral
syms g;
g=u^2;

%Hamiltonian
syms p1 p2 H;
H=g+p1*Dx1+p2*Dx2;

%Costate equations
Dp1=-diff(H,x1);
Dp2=-diff(H,x2);

%Solve for control u
du=diff(H,u);
sol_u=solve(du,´u´);

%Substitute u to state equations
Dx1=subs(Dx1,u,sol_u);

%Convert symbolic objects to strings for using dsolve
eq1=strcat(´Dx1=´,char(Dx1));
eq2=strcat(´Dx2=´,char(Dx2));
eq3=strcat(´Dp1=´,char(Dp1));
eq4=strcat(´Dp2=´,char(Dp2));
sol_h=dsolve(eq1,eq2,eq3,eq4);

% for boundary conditions : x1(0)=x2(0)=0;x1(2)=x2(2)=0.5;
conA1=´x1(0)=0´;
conA2=´x2(0)=0´;
conA3=´x1(2)=0.5;
conA4=´x2(2)=0.5;
sol_a=dsolve(eq1,eq2,eq3,eq4,conA1,conA2,conA3,conA4);

AND HOW TO PLOT A GRAPH FOR STATE-TIME?