Hi
How can I plot a f(t)=t^3 when with a period of -pi<=t<pi.
Over the time interval of -2pi<=t<=2pi.
MATLAB: Plotting quadratic f(t) = t^3
equationSignal Processing Toolbox
Related Solutions
It sounds to me like you might be attempting to solve exp(-0.01*t.^2).*cos(2.*t) to find the t where the expression becomes 0.4 . If so then there are an infinite number of solutions. You can find one of them by using
syms f(t)f(t) = exp(-0.01*t.^2).*cos(2.*t);vpasolve(f(t)=0.4)I don't know what's C8 and should I just take the (-exp(2*C8 + 2*t)/(exp(2*C8 + 2*t) - 1))^(1/2) as the correct solution?
Yes? No?
C8 represents a constant needed to represent a boundary condition.
syms x(t) x0dx = diff(x)
eqn = dx == x(t)+(x(t))^3
X = simplify(dsolve(eqn, x(0)==x0)) %boundary condition on x(0)
subs(X,t,0) %crosscheck
Oh dear, that loses the sign. What happens if x0 was negative?
Xneg = dsolve(eqn, x(0)==-2)Xpos = simplify(dsolve(eqn, x(0)==2))
fplot(Xpos, [0 1])
The larger the boundary condition, the smaller the distance until the singularity. For small enough boundary conditions, the distance to the singularity is approximately -log(sqrt(x0)) -- for boundary conditions of the form 1/N for large enough N, that would be very close to log(sqrt(N))
Best Answer