Hey! I am new to matlab and I need some help here.

So this is the problem: Write an equation that plots the quadratic formula, linearly spaced with 100 divisions. The equation for a particular quadratic expression should be in the form ax^2 +b^x + c,with the bounds on x are x1 and x2 where i t is assumed that x1 < x2. Using the functions linspace and plot may prove to be helpful as well as the hold switch. Make sure you include a title on the plot.

ANY HELP would be really appreciated!

[Image Analyst]

Here's some help: http://www.mathworks.com/matlabcentral/answers/8626-how-do-i-get-help-on-homework-questions-on-matlab-answers. Basically you're supposed to at least do a little coding and ask specific, targeted questions, rather than just tell us the problem statement.

Answer 1

[Mohammad Abouali]

% Let's say:
a=3;
b=2;
c=1;
% we have y= ax^2 + bx + c;
% so the function to plot would be y=3x^2+2x+1;

p=[a, b, c];

% now let's say:
x1=-10;
x2=10;
n=100; %number of samples

x=linspace(x1,x2,n);
y=polyval(p,x);

plot(x,y)
title(sprintf('y= %fx^2 + %fx + %f',p(1),p(2),p(3)))

You can write that in function form as follows:

function myPlot(a,b,c,x1,x2,n)
  p=[a, b, c];
  x=linspace(x1,x2,n);
  y=polyval(p,x);

    plot(x,y)
    title(sprintf('y= %fx^2 + %fx + %f',p))
  end

Now you can call it as follow

myPlot(3,2,1,-10,10,100);

Answer 2

[Naeem Roshan]

introduce x and find y=ax^2+b^x+c (put numbers you want in place of x1,x2,step,a,b,c)

x = linespace(x1,x2,step);
y = a*x.^2 + b*x + c;

plot and its title

plot(x,y)
title('your title')

I hope this would be helpful :)

[Image Analyst]

linspace, not linespace