MATLAB program to find the roots of an equation

Write a MATLAB program to find the roots of the following equation for 0.2≤C≤2 (take ∆ C=0.1). Then plot the obtained roots versus the constant C. cos(x)=C*x

That's my try and I don't know what I did wrong

[Steven Lord]

This sounds like a homework assignment. If you show us what you've tried already to solve the problem and ask a specific question about where you're having difficulty we may be able to offer suggestions for how to proceed.

[Mohamed Adel]

I tried to use fsolve to determine the roots but I didn't get the roots That's my try I don't know what I did wrong

Answer 1

[Basil C.]

Instead of using fsolve try using vpasolve

syms x
c=0.2:0.1:2;
y=cos(x)-c*x;
for i=1:numel(y)
  sol(i)=vpasolve(y(i),x);
end

Now you can continue with plotting the graph

the approximate solution of each equation is stored in the variable sol

[Mohamed Adel]

Thank you so much,Basil. I understood it.