Find and display intersections using fzero
59 views (last 30 days)
Show older comments
I have two functions: f(x) = x.^2-1, f(g) = exp(x/5) in a linspace(-2,2). I need to indicate on the graph where f = g using the fzero function. Also I would like to keep it in a single m file.
Thanks
0 Comments
Accepted Answer
Brendan Hamm
on 12 Mar 2015
Edited: Brendan Hamm
on 12 Mar 2015
If f(x) = g(x) then f(x) - g(x) = 0. So we need to define h(x) = f(x) - g(x) and find where h(x) = 0. This is exactly what fzero is made for.
h = @(x) x.^2 - 1 - exp(x/5); % Creates a function handle for your function
Now let's plot and see if we can find a point close to where this function is zero.
x = -2:0.01:2;
plot(x,h(x));
Looks like -1.5 and 1.5 are close.
firstZero = fzero(h,-1.5);
secondZero = fzero(h,1.5);
Now visualize these on the plot:
hold on
plot(firstZero,h(firstZero),'ro');
plot(secondZero,h(secondZero),'ro');
hold off
2 Comments
Brendan Hamm
on 13 Mar 2015
Awesome. If you found this to solve your problem, please accept the answer so others with similar issues can find the solution.
More Answers (0)
See Also
Categories
Find more on 2-D and 3-D Plots in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!