Question: Difficulty Graphing First & Second Derivative Tests

Hi

I am having difficulty graphing.

I am posting my Maple fileView 1327_First & Second Derivatives Tests.mw on MapleNet or Download 1327_First & Second Derivatives Tests.mw
View file details.

Please let me know why my following commands are not working

a := plot(f(x), x = 0 .. 6); b := plot(Df(x), x = 0 .. 6, linestyle = 2); c1 := plot([subs({z = -3}, critpts[1]), t, t = -6 .. 6], color = green); c2 := plot([subs({z = -3}, critpts[2]), t, t = -6 .. 6], color = green); c3 := plot([critpts[3], t, t = -6 .. 6], color = green); c4 := plot([subs({z = -2}, critpts[2]), t, t = -6 .. 6], color = green); c5 := plot([subs({z = -1}, critpts[2]), t, t = -6 .. 6], color = green); c6 := plot([subs({z = 0}, critpts[2]), t, t = -6 .. 6], color = green); c7 := plot([subs({z = -2}, critpts[1]), t, t = -6 .. 6], color = green); display([a, b, c1, c2, c3, c4, c5, c6, c7], title = `function in solid, derivative in dotted`)

a := plot(f(x), x = -1 .. 5, y = -15 .. 15); b := plot(Df(x), x = -1 .. 5, y = -15 .. 15, linestyle = 2); c := plot(DDf(x), x = -1 .. 5, y = -15 .. 15, linestyle = 3); display([a, b, c], title = `function in solid, 1st deriv in dotted, 2nd deriv dashed`)

a := plot(f(x), x = -1 .. 5, y = -15 .. 15); b := plot(Df(x), x = -1 .. 5, y = -15 .. 15, linestyle = 2); c := plot(DDf(x), x = -1 .. 5, y = -15 .. 15, linestyle = 3); display([a, b, c], title = `function in solid, 1st deriv in dotted, 2nd deriv dashed`)

a := plot(f(x), x = -2 .. 7, y = -10 .. 10); b := plot(Df(x), x = -2 .. 7, y = -10 .. 10, linestyle = 2); c := plot(DDf(x), x = -2 .. 7, y = -10 .. 10, linestyle = 3); display([a, b, c], title = `function in solid, 1st deriv in dotted, 2nd deriv dashed`)

Waiting for your reply

Take care