function xdot=xprime(t,x,F)
M = 1.096;
m = 0.109;
b = 0.1;
I = 0.0034;
f=0;
g = 9.8;
l = 0.25;
D1=(F+m*l*sin(x(3))*(x(4))^2-b*x(2))*(m*l^2+I)-(m*g*l*sin(x(3))-f*x(4))*m*l*cos(x(3));
D=(m+M)*(m*l^2+I)-(m*l*cos(x(3)))^2;
D2=(m+M)*(m*g*l*sin(x(3))-f*x(4))-(m*l*cos(x(3)))*(F+m*l*sin(x(3))*(x(4))^2-b*x(2));

xdot=zeros(4,1);
xdot(1)=x(2);
xdot(2)=D1/D;
xdot(3)=x(4);
xdot(4)=D2/D;