Plotting a Differential Equation with respect to time.

Greetings. I have a non-linear ODE that I want to solve given the parameters. I am familiar with solving ODEs using 'dsolve' and 'ode45' functions, but I do not know how to plot the parameters with respect to time. I have uploaded a picture of my assignment to make things clear, can anyone help me with that? Thank you very much in advance.

Answer 1

[Ngoc Thanh Hung Bui]

%% in dsolve you just need to plot the solution with the time, for example:

syms theta(t)

sol = dsolve(...)

t= 0:1:40;

plot(t, sol)

but the given equation contain sin(theta) so there is no analytic solution for it, so dsolve isnt appropriated here

%% in the ode45 function there is a paramether for time, for example:

tspan = 0:1:40;

init = [1 0];

[t,y] = ode45(@pendulum, tspan, init);

plot(t,y)