matlab用二分法求解x^2+8*x+3=0,二分法进行编码

以下是使用 MATLAB 实现二分法求解 x^2 + 8*x + 3 = 0 的代码：

function [root, iter] = bisection(f, a, b, tol, maxiter)
% f: the function to be solved
% a, b: the interval to search for root
% tol: the tolerance for the root
% maxiter: the maximum number of iterations allowed

% check if the function has different signs at the endpoints
if f(a) * f(b) >= 0
error('The function has the same sign at the endpoints.');
end

% initialize the variables
iter = 0;
root = (a + b) / 2;

% iterate until the root is found or the maximum number of iterations is reached
while abs(f(root)) > tol && iter < maxiter
if f(a) * f(root) < 0
b = root;
else
a = root;
end
root = (a + b) / 2;
iter = iter + 1;
end

% check if the maximum number of iterations is reached
if iter == maxiter
warning('The maximum number of iterations is reached.');
end

end

% call the function with the given parameters
f = @(x) x^2 + 8*x + 3;
a = -10;
b = 10;
tol = 1e-6;
maxiter = 100;
[root, iter] = bisection(f, a, b, tol, maxiter);

% print the result
fprintf('The root is %f, found after %d iterations.\n', root, iter);