I have made the plot of the function and arrow separately and then displayed them together. As far as the arrow is concerned, we need to practice or know the terms thoroughly to get the correct plot with correct arrows.
I have made a single plot and two plots as well in separately for a better uderstanding.
Arrow commands are individually made to ensure the shape coicides with curves. Once experienced, you can directly enter the correct arrow command to make it inline with curve.
b1 := plot(x^2, x = 0.. 5)
b2 := arrow(<5, 5^2>, <0.1, 1>, width = 0.05, color = red)
display(b1, b2, scaling = unconstrained)
Another Plots (two graphs)
a1 := plot([x^2, (x + 1)^2], x = 0 .. 10);
b2 := arrow(<10, 10^2>, <1, 16>, width = 0.1, color = red);
b3 := arrow(<10, 11^2>, <1, 18>, width = 0.1, color = blue);
display(a1, b2, b3, scaling = unconstrained);
Hope this contributes at least to a little extent.