MATLAB: Getting the Incorrect Plot

plotplot functionsimple question

I have a function (func) given to me with desired x-values (x). The assignment is to plot func while also plotting the x-intercepts. It appears to me that I am getting the correct values when I check the x/y data points, but the graph does not line up.
x = -10:.1:8;
func = (x-6).*((x.^2)-1).*(x+8);
plot(func);
title("Graph of Function");
xlabel("Vector Values");
ylabel("Function Values");
hold on;
%Plots the x-intercepts
[~,cols] = size(func);
for i=1:cols 
    if func(i) == 0
        plot(x(i),0,'*r')
    end
end
The x-intercepts are correct and the data points are correct; however, my plot does not line up. Not sure what is wrong. Any help would be great!

Best Answer

x = -10:.1:8;
func = (x-6).*((x.^2)-1).*(x+8);
plot(x,func);
title("Graph of Function");
xlabel("Vector Values");
ylabel("Function Values");
hold on;
%Plots the x-intercepts
indx = find(func==0);
plot(x(indx),zeros(1,numel(indx)),'*')
edit: what went wrong is that you didnt plot(x,func) in the beginning, so the scaling of the x axis was different.
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