[size=200][color=#000000]Define the integral function integral[f,a,x].[br]Simulate the mechanical device 'Integraph', plotting the graph of the integral function integral[f,a,x] just until x = x(S).[br][br]Investigating the slope of the integral function: [b]Fundamental Theorem of calculus[/b], detectable by students![/color][/size][br][br]