f = x*cos(x)^2

plotf = plot(f, (x,-1,3.5), color='purple', thickness=3)

origin = point((0,0), color='orange', alpha=.7, size=150)

label = 'MacLaurin polynomial of $%s$ of degree'%latex(f)

@interact

def _(j=slider(0, 20, 1, default=3, label=label)):

    Tjf = f.taylor(x, 0, j)

    plotTjf = plot(Tjf, (x,-1,3.5), color='green', thickness=1.5, fill=f)

    pretty_print(latex(Tjf))

    show(plotf + plotTjf + origin, ymin=-0.5, ymax=3.5, figsize=[7,3])