function y=func()
clc
clear
syms t a0 a1 a2 a3 a4 a5 a6 a7 a8 b1 b2 b3 b4 b5 b6 b7 b8;
epsilon=0.125;
alpha=1.0;
omega=2.0;
gamma=1.0;
beta=4.6;
x=a0+a1*cos(t)+a2*cos(2*t)+b1*sin(t)+b2*sin(2*t);
%x=a0+a1*cos(t)+a2*cos(2*t)+a3*cos(3*t)+a4*cos(4*t)+a5*cos(5*t)+a6*cos(6*t)+a7*cos(7*t)+a8*cos(8*t)+b1*sin(t)+b2*sin(2*t)+b3*sin(3*t)+b4*sin(4*t)+b5*sin(5*t)+b6*sin(6*t)+b7*sin(7*t)+b8*sin(8*t);
% f=diff(diff(x,t),t)+2*epsilon*diff(x,t)-(alpha+beta*sin(omega*t))*x-gamma*x^3;
%f=omega^2*diff(diff(x,t),t)+2*omega*epsilon*diff(x,t)-(alpha+beta*sin(t))*x-gamma*x^3
d_x=diff(x,'t');
dd_x=diff(d_x,'t');
f=omega^2*dd_x+2*epsilon*omega*d_x-(alpha+beta*sin(t))*x+gamma*x^3
f_1=simplify(int(f,t,0,2*pi)/(2*pi));
f_cost=simplify(int(f*cos(t),t,0,2*pi)/pi);
f_cos2t=simplify(int(f*cos(2*t),t,0,2*pi)/pi);
f_sint=simplify(int(f*sin(t),t,0,2*pi)/pi);
f_sin2t=simplify(int(f*sin(2*t),t,0,2*pi)/pi);
% fun=[f_1;f_cost;f_cos2t;f_sint;f_sin2t]
% x0(5)=0
% Newtons(fun,x0)
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