First Order ODE

Solve in Matlab

• solve 1st order differential equation : $$\frac{dx}{dt} = 3e^{-t}$$, and initial x(0) = 0

• matlab code

function test1
    % solv dx/dt = 3 exp (-t)
    % init x(0) = 0

    t = 0:0.001:5;
    init_x = 0;

    [t, x] = ode45(@rhs, t, init_x);
    plot(t,x);
    xlabel('t');
    ylabel('x');

    function dxdt = rhs(t, x)
        dxdt = 3 * exp (-t);
    end
end

• the result