ode 45 doesnt work

Hey' so im tring to solve this eq

this is the code' what im missing? why it dosent work?

y0 = [-1 ;8]; 
tspan = [0 ;3];
[t,y] = ode45(@(t,y) ((2*y^2*t + 4)/((3-t^2*y)*2)),tspan,y0);
plot(t,y)
grid on
xlabel('t')
ylabel('y')
title('Solutions of (2*y^2*t + 4)/((3-t^2*y)*2','interpreter','latex')

Answer 1

[William Rose]

@Naor t,

It doesn;t work because you define y0=[-1 8], a vector with 2 elements. Therefore ode45() gets into trouble when it tries to square this vector as it evaluates dydt.

If you define y0=-1 it works. See result below.

Answer 2

[Cris LaPierre]

There is an issue with your initial conditions. See this post on how to set up an initial value problem when t ~= 0.

However, you may want to revisit either your equation or your initial values, as the result seems incorrect. Y values are extremely big.

y0 = 8; 
tspan = [-1 3];
[t,y] = ode45(@(t,y) ((2*y^2*t + 4)/((3-t^2*y)*2)),tspan,y0);
plot(t,y)
grid on
xlabel('t')
ylabel('y')
title('Solutions of (2*y^2*t + 4)/((3-t^2*y)*2')