%syms x;
%g=@(x) (-2*x^2+x+3)^(1/4);
%y(1)=0;
%y(2)=subs(g,x,y(1));
%k=2;
%while abs(y(k)-y(k-1))>=10^(-5)
%    k=k+1;
%    y(k)=subs(g,x,y(k-1));
%end
%xaprox=y(k)
%k
%syms a;
%f=@(a) a.^4+2*a.^2-a-3;
%X=linspace(-1,3/2,100);
%Y=f(X);
%plot(X,Y);
%hold on;
%plot(xaprox,f(xaprox),'o','MarkerSize' ,10,'MarkerFaceColor','g');
%hold off;


x(1:2,1)=[0.5,0.5];
x(:,2)=[(x(1,1)^2+x(2,1)^2+8)/10; (x(1,1)*x(2,1)^2+x(1,1)+8)/10];
k=2;
while norm(x(:,k)-x(:,k-1),inf)>=10^(-5)
    k=k+1;
    x(:,k)=[(x(1,k-1)^2+x(2,k-1)+8)/10;(x(1,k-1)*x(2,k-1)^2+x(1,k-1)+8)/10];
end
xaprox=x(:,k);
k

%F1(x1,x2)=1^2-10x1+x2^2+8=0
%F2(x1,x2)=x1x2^2+x1-10x2+8=0

syms x y
F1=x^2-10*x+y^2+8;
F2=x*y^2+x-10*y+8;
ezplot(F1,[-20,20,-20,20]);
hold on;
ezplot(F2,[-20,20,-20,20]);
plot(xaprox(1,1),xaprox(2,1),'o','MarkerFaceColor','m','MarkerSize',10);
hold off;