How do I find all the positive roots of (e^(-.2x ))(cos(2x))-.15x^2+1

3 views (last 30 days)
So far, I've done
fun=@(x) exp^(-.2*x)*cos(2*x)-.15*x^(2)+1;
x0=[-6: .1 :6];
z=fzero(fun,x0);
Nothing happens.

Answers (1)

Seth DeLand
Seth DeLand on 10 Apr 2013
2 things: 1) fzero is designed to find a single zero at a time. You will need to loop through each value for x0 and record the zero the fzero found for that starting point. Something like:
for i = 1:length(x0)
z(i) = fzero(fun, x0(i));
end
2) exp is a function that expects 1 input, if you want to calculate e^(-.2x) you can write:
exp(-.2*x)

Categories

Find more on Loops and Conditional Statements 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!