БДЗ2 / Метод хорд

Код:

clc,clear

syms x

fun = x.^5 - 2*sin(x);

a = 0;

b = 1;

e = 0.001;

%der = diff(fun);

der = 5*x^4 - 2*cos(x);

%xmin = a - (subs(der,a)/(subs(der,a) - subs(der,b)))*(a-b);

xmin = a - ((5*a.^4-2*cos(a))/((5*a.^4-2*cos(a)) - (5*b.^4-2*cos(b)))*(a-b));

fmin = subs(fun,xmin);

A = [];

B = [];

while abs(subs(der,xmin))>=e

%xmin = a - (subs(der,a)/(subs(der,a) - subs(der,b)))*(a-b);

xmin = a - ((5*a.^4-2*cos(a))/((5*a.^4-2*cos(a)) - (5*b.^4-2*cos(b)))*(a-b));

%der_v = subs(der,xmin);

der_v = 5*xmin.^4 - 2*cos(xmin);

if der_v>0

b = xmin;

else

a = xmin;

end

A(end+1) = xmin;

%B(end+1) = subs(fun,xmin);

B(end+1) = xmin.^5 - 2*sin(xmin);

end

A((end-2):end)

B((end-2):end)

xmin

fmin = subs(fun,xmin)

Результат:

ans = 0.7370 0.7374 0.7375

ans = -1.1267 -1.1267 -1.1267

xmin = 0.7375

fmin = -1.1267