How to solve this equation

I need to solve the following differntinal equation:

y' = -(1+2n)y

intial condition y(0)=1 , n=1

[John D'Errico]

Surely you need to do your own homework assignment?

[Raef]

Its not my homework assignment, my dad is an applied mathematics scientist and has other colleagues that do the computer work which he don't know how to use. So im trying to learn to use matlab to help and contribute so this is the simple equation he gave me to solve and see if I get a result

Answer 1

[Sam Chak]

@Raef, you are a good son and took up a filial duty to help your father.

n  = 1;
y0 = 1;     % intial value
F  = @(t, y) - (1 + 2*n)*y;
[t, y] = ode45(F, [0 5], y0);
plot(t, y), grid on, xlabel('t'), ylabel('y(t)')

[Raef]

Thanks a lot for your words and answer

Answer 2

[Torsten]

Use pencil and paper.

dy/dt = -(1+2*n)*y
-> dy/y = -(1+2*n)*dt
-> log(y/y0) = -(1+2*n)*(t-t0)
-> y = ?

[Raef]

Thanks for the response, but i needed done as a graph on matlab

[Torsten]

If you know the explicit form of the solution like from the approach with paper and pencil, you can easily graph it.

If you also have to derive the solution with a MATLAB solver, either use "dsolve" or "ode45".

[Raef]

Thanks