Thank you for Assisting me to solve the PDE, Now please would you tell me what F5 means (in other words, explain to me the solution) and also could you how to test if the solution satisfies the initial and boundary conditions.

Please help me plot the graphs of the following equations:-

eq1 := diff(E[X(t)], t) = lambda-delta*E[X(t)]-beta*E[X(t)*V(t)];

 eq2 := diff(E[Y(t)], t) = -delta*E[Y(t)]+beta*exp(-rho*tau)*E[X(t)*V(t)];
                                                    
eq3 := diff(E[V(t)], t) = gamma+N*kappa*E[Y(t)]-mu*E[V(t)]-beta*E[X(t)*V(t)]

NB:- E[X(t)]= the expected value of variable X at time t. 

Please help me know how to input this...

How can i solve for G(p,q,r,t) in the following pde

diff(G(p, q, r, t), t) = {lambda*(p-1)+gamma*(r-1)}*G(p, q, r, t)+delta*(1-p)*(diff(G(p, q, r, t), p))+kappa*(N*r-q)*(diff(G(p, q, r, t), q))+mu*(1-r)*(diff(G(p, q, r, t), r))+beta*(q*e^(-`ρτ`)-p*r)*(diff(G(p, q, r, t), r, p))

How can i solve for X(t) in the following equation

diff(mean(X(t)), t) = lambda-delta*mean(X(t))-beta*mean(X(t)*V(t))

and how can i plot X(t) against t.