(sorry, I know that I am only supposed to submit one question. but i couldn't find a way to break it up)

Using MatLab:

5. Follow the following instruction to plot.

a) Create a meshgrid using x values with range(0 to 2pi,with an interval 0.05pi) and y values with the range(0 to 1, with an interval 0.05). (hint: [xx yy]=meshgrid(x,y))

b) Define the following variables: c=[0.1 + 0.9 * (pi - abs(xx-pi))/(pi)] .*yy

a = c.* cos(xx)

b = c.* sin * (xx)

z = (-2) * a.^3 + (3/2) * c.^2 + 0.5

c) Plot z against a and b using the surf() function with interpolated colors.

(Hint: in the end, add view(-30,50) will give you a better view to see the drawing)