Suppose I have a vector-valued function $f(x)$, and want to plot each component with respect to $x$.
If I try, as stated in the documentation,
Foo[inp_] := {Sin[inp], Cos[inp], Tan[inp]}
Plot[Foo[n], {n, 0, Pi/2}, PlotLegends -> Automatic]
I get a single-coloured plot without any legend. How can I add a legend saying which curve is which component? (I have tried PlotLegends-> "Expressions", which also didn't work)